Level 1, 2, 3, 4, and 5 SAT Math Problems
Legal Notice
This book is copyright 2012 with all rights reserved. It is illegal to copy,
distribute, or create derivative works from this book in whole or in part
or to contribute to the copying, distribution, or creating of derivative
works of this book.
iii
A Proven Roadmap to
Your First-Choice College
Steve Warner, Ph.D.
© 2012, All Rights Reserved
SATPrepGet800.com © 2013
iv
This book is dedicated to all my students over the past
12 years, I have learned just as much from all of you as
you have learned from me.
I would also like to acknowledge Larry Ronaldson and Robert
Folatico, thank you for introducing me to the rewarding field of
SAT tutoring.
BOOKS BY DR. STEVE WARNER FOR COLLEGE BOUND STUDENTS
28 SAT Math Lessons to Improve Your Score in One Month
Beginner Course
Intermediate Course
Advanced Course
320 SAT Math Problems Arranged by Topic and Difficulty Level
SAT Prep Book of Advanced Math Problems
The 32 Most Effective SAT Math Strategies
SAT Prep Official Study Guide Math Companion
ACT Prep Red Book – 320 ACT Math Problems with Solutions
CONNECT WITH DR. STEVE WARNER
v
Table of Contents
Introduction: The Proper Way to Prepare 7
1. The magical mixture for success 7
2. Practice problems of the appropriate level 9
3. Practice in small amounts over a long period of time 9
4. Redo the problems you get wrong over and over and
over until you get them right 10
5. Check your answers properly 10
6. Guess when appropriate 11
7. Pace yourself 11
8. Attempt the right number of questions 12
9. Use your calculator wisely 13
10. Grid your answers correctly 14
Problems by Level and Topic with Fully Explained Solutions 17
Level 1: Number Theory 17
Level 1: Algebra and Functions 23
Level 1: Geometry 28
Level 1: Probability and Statistics 34
Level 2: Number Theory 40
Level 2: Algebra and Functions 46
Level 2: Geometry 52
Level 2: Probability and Statistics 58
Level 3: Number Theory 64
Level 3: Algebra and Functions 72
Level 3: Geometry 79
Level 3: Probability and Statistics 86
Level 4: Number Theory 92
Level 4: Algebra and Functions 99
Level 4: Geometry 104
Level 4: Probability and Statistics 110
Level 5: Number Theory 117
Level 5: Algebra and Functions 125
Level 5: Geometry 133
Level 5: Probability and Statistics 142
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Supplemental Problems – Questions 149
Level 1: Number Theory 149
Level 1: Algebra and Functions 150
Level 1: Geometry 152
Level 1: Probability and Statistics 155
Level 2: Number Theory 156
Level 2: Algebra and Functions 158
Level 2: Geometry 160
Level 2: Probability and Statistics 163
Level 3: Number Theory 165
Level 3: Algebra and Functions 166
Level 3: Geometry 169
Level 3: Probability and Statistics 172
Level 4: Number Theory 174
Level 4: Algebra and Functions 176
Level 4: Geometry 178
Level 4: Probability and Statistics 181
Level 5: Number Theory 183
Level 5: Algebra and Functions 185
Level 5: Geometry 187
Level 5: Probability and Statistics 190
Answers to Supplemental Problems 194
Afterword: Your Road to Success 201
About the Author 203
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I N T R O D U C T I O N
THE PROPER WAY TO PREPARE
here are many ways that a student can prepare for the SAT.
But not all preparation is created equal. I always teach my students the
methods that will give them the maximum result with the minimum
amount of effort.
In “The 32 Most Effective SAT Math Strategies” I emphasize the
most important techniques for this particular test. That book contains
115 problems that are perfect for implementing the various strategies
discussed there. In fact, using that book alone is enough to significantly
boost anyone’s SAT math score.
The book you are now reading is also self-contained. Each problem
was carefully created to ensure that you are making the most effective
use of your time while preparing for the SAT. By grouping the problems
given here by level and topic I have ensured that you can focus on the
types of problems that will be most effective to improving your score.
1. The magical mixture for success
A combination of three components will maximize your SAT math score
with the least amount of effort.
Learning test taking strategies that are specific to the SAT.
Practicing SAT problems for a small amount of time each day for
about three months before the SAT.
Taking about four practice tests before test day to make sure
you are applying the strategies effectively under timed
conditions.
I will discuss each of these three components in a bit more detail.
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Strategy: The more SAT specific strategies that you know the better off
you will be. All the strategies you need to know are in “The 32 Most
Effective SAT Math Strategies,” as well as 115 problems to practice
implementing these strategies. Note that it is not enough to know these
strategies. You must practice using them on SAT problems as often as
possible.
Practice: The book you are now reading is ideal for accomplishing this
task. The problems given in this book are more than enough to vastly
improve your current SAT math score. All you need to do is work on
these problems for about ten to twenty minutes each day over a period
of three to four months and the final result will far exceed your
expectations.
Let me further break this component into two subcomponents – topic
and level.
Topic: You want to practice each of the four general math topics
given on the SAT and improve in each independently. The four topics are
Number Theory, Algebra and Functions, Geometry, and Probability and
Statistics. The problem sets in this book are broken into these four
topics.
Level: You will make the best use of your time by primarily
practicing problems that are at and slightly above your current ability
level. For example, if you are struggling with Level 2 Geometry problems,
then it makes no sense at all to practice Level 5 Geometry problems.
Keep working on Level 2 until you are comfortable, and then slowly
move up to Level 3. Maybe you should never attempt those Level 5
problems. You can get an exceptional score without them (higher than
700).
Tests: You want to take about four practice tests before test day to
make sure that you are implementing strategies correctly and using your
time wisely under pressure. For this task you should use the second
edition of “The Official SAT Study Guide” by the College Board. Take one
test every few weeks to make sure that you are implementing all the
strategies you have learned correctly under timed conditions. Note that
only the second edition has three actual SATs.
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2. Practice problems of the appropriate level
Roughly speaking about one third of the math problems on the SAT are
easy, one third are medium, and one third are hard. If you answer two
thirds of the math questions on the SAT correctly, then your score will
be approximately a 600 (out of 800). That’s right—you can get about a
600 on the math portion of the SAT without answering a single hard
question.
Keep track of your current ability level so that you know the types of
problems you should focus on. If you are currently scoring around a 400
on your practice tests, then you should be focusing primarily on Level 1,
2, and 3 problems. You can easily raise your score 100 points without
having to practice a single hard problem.
If you are currently scoring about a 500, then your primary focus should
be Level 2 and 3, but you should also do some Level 1 and 4 problems.
If you are scoring around a 600, you should be focusing on Level 2, 3,
and 4 problems, but you should do some Level 1 and 5 problems as well.
Those of you at the 700 level really need to focus on those Level 4 and 5
problems.
If you really want to refine your studying, then you should keep track of
your ability level in each of the four major categories of problems:
Number Theory
Algebra and Functions
Probability, Statistics and Data Analysis
Geometry
For example, many students have trouble with very easy geometry
problems, even though they can do more difficult number theory
problems. This type of student may want to focus on Level 1, 2, and 3
geometry questions, but Level 3 and 4 number theory questions.
3. Practice in small amounts over a long period of time
Ideally you want to practice doing SAT math problems ten to twenty
minutes each day beginning at least 3 months before the exam. You will
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retain much more of what you study if you study in short bursts than if
you try to tackle everything at once.
The only exception is on a day you do a practice test. You should do at
least four practice tests before you take the SAT. Ideally you should do
your practice tests on a Saturday or Sunday morning. At first you can do
just the 3 math sections. The last one or two times you take a practice
test you should do the whole test in one sitting. As tedious as this is, it
will prepare you for the amount of endurance that it will take to get
through this exam.
So try to choose about a twenty minute block of time that you will
dedicate to SAT math every night. Make it a habit. The results are well
worth this small time commitment.
4. Redo the problems you get wrong over and over and
over until you get them right
If you get a problem wrong, and never attempt the problem again, then
it is extremely unlikely that you will get a similar problem correct if it
appears on the SAT.
Most students will read an explanation of the solution, or have someone
explain it to them, and then never look at the problem again. This is not
how you optimize your SAT score. To be sure that you will get a similar
problem correct on the SAT, you must get the problem correct before
the SAT—and without actually remembering the problem.
This means that after getting a problem incorrect, you should go over
and understand why you got it wrong, wait at least a few days, then
attempt the same problem again. If you get it right you can cross it off
your list of problems to review. If you get it wrong, keep revisiting it
every few days until you get it right. Your score does not improve by
getting problems correct. Your score improves when you learn from
your mistakes.
5. Check your answers properly
When you go back to check your earlier answers for careless errors do
not simply look over your work to try to catch a mistake. This is usually a
waste of time. Always redo the problem without looking at any of your
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previous work. Ideally, you want to use a different method than you
used the first time.
For example, if you solved the problem by picking numbers the first
time, try to solve it algebraically the second time, or at the very least
pick different numbers. If you don’t know, or are not comfortable with a
different method, then use the same method, but do the problem from
the beginning and do not look at your original solution. If your two
answers don’t match up, then you know that this a problem you need to
spend a little more time on to figure out where your error is.
This may seem time consuming, but that’s ok. It is better to spend more
time checking over a few problems than to rush through a lot of
problems and repeat the same mistakes.
6. Guess when appropriate
Answering a multiple choice question wrong will result in a 1/4 point
penalty. This is to discourage random guessing. If you have no idea how
to do a problem, no intuition as to what the correct answer might be,
and you can’t even eliminate a single answer choice, then DO NOT just
take a guess. Omit the question and move on.
If, however, you can eliminate even one answer choice, you should take
a guess from the remaining four. You should of course eliminate as many
choices as you can before you take your guess.
You are not penalized for getting a grid-in question wrong. Therefore
you should always guess on grid-in questions that you don’t know. Never
leave any of these blank. If you have an idea of how large of a number
the answer should be, then take a reasonable guess. If not, then just
guess anything—don’t think too hard—just put in a number.
7. Pace yourself
Do not waste your time on a question that is too hard or will take too
long. After you’ve been working on a question for about 1 minute you
need to make a decision. If you understand the question and think that
you can get the answer in another 30 seconds or so, continue to work on
the problem. If you still don’t know how to do the problem or you are
using a technique that is going to take a long time, mark it off and come
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back to it later if you have time.
If you have eliminated at least one answer choice, or it is a grid-in, feel
free to take a guess. But you still want to leave open the possibility of
coming back to it later. Remember that every problem is worth the same
amount. Don’t sacrifice problems that you may be able to do by getting
hung up on a problem that is too hard for you.
8. Attempt the right number of questions
There are three math sections on the SAT. They can appear in any order.
There is a 20 question multiple choice section, a 16 question multiple
choice section, and an 18 question section that has 8 multiple choice
questions and 10 grid-ins.
Let us call these sections A, B, and C, respectively. You should first make
sure that you know what you got on your last SAT practice test, actual
SAT, or actual PSAT (whichever you took last). What follows is a general
goal you should go for when taking the exam.
Score Section A Section B Section C
(Multiple
choice)
Section C
(Grid-in)
< 330 7/20 6/16 2/8 2/10
330 – 370 10/20 8/16 3/8 3/10
380 – 430 12/20 10/16 4/8 4/10
440 – 490 14/20 11/16 5/8 6/10
500 – 550 16/20 12/16 6/8 8/10
560 – 620 18/20 15/16 7/8 9/10
630 – 800 20/20 16/16 8/8 10/10
For example, a student with a current score of 450 should attempt the
first 14 questions from section A, the first 11 questions from section B,
the first 5 multiple choice questions from section C, and the first 6 gridins from section C.
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This is just a general guideline. Of course it can be fine-tuned. As a
simple example, if you are particularly strong at number theory
problems, but very weak at geometry problems, then you may want to
try every number theory problem no matter where it appears, and you
may want to reduce the number of geometry problems you attempt.
9. Use your calculator wisely.
It is recommended that you use a TI-84 or comparable calculator for the
SAT. It is important that you are comfortable with your calculator on test
day, so make sure that you are consistently practicing with the calculator
you plan to use. Make sure that your calculator has fresh batteries the
day of the test. Nobody will supply a calculator for you if yours dies.
Below are the most important things you should practice on your
graphing calculator.
(1) Practice entering complicated computations in a single step, and
know when to insert parentheses. In general, there are 4 instances when
you should use parentheses in your calculator.
Around numerators of fractions
Around denominators of fractions
Around exponents
Whenever you actually see parentheses in the expression
Examples:
We will substitute a 5 in for x in each of the following examples.
Expression Calculator computation
11 2
3 7
x
x
(7*5 + 3)/(2*5 – 11)
9 2
) 8 3 (
x
x
(3*5 – 8)^(2*5 – 9)
(2) Clear the screen before using it in a new problem. The big screen
allows you to check over your computations easily.
(3) Press the ANS button (2
nd
(-) ) to use your last answer in the next
computation.
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(4) Press 2
nd
ENTER to bring up your last computation for editing. This is
especially useful when you are plugging in answer choices, or guessing
and checking.
(5) You can press 2
nd
ENTER over and over again to cycle backwards
through all the computations you have ever done.
(6) Know where the ,
, and ^ buttons are so you can reach them
quickly.
(7) Change a decimal to a fraction by pressing MATH ENTER ENTER.
(8) Press the MATH button - in the first menu that appears you can take
cube roots and nth roots for any n. Scroll right to PRB and you have nPr
and nCr to compute permutations and combinations very quickly.
The following items are less important but can be useful.
(9) Press the Y= button to enter a function, and then hit ZOOM 6 to
graph it in a standard window.
(10) Practice using the WINDOW button to adjust the viewing window of
your graph.
(11) Practice using the TRACE button to move along the graph and look
at some of the points plotted.
(12) Pressing 2nd TRACE (which is really CALC) will bring up a menu of
useful items. For example selecting ZERO will tell you where the graph
hits the x-axis, or equivalently where the function is zero. Selecting
MINIMUM or MAXIMUM can find the vertex of a parabola. Selecting
INTERSECT will find the point of intersection of 2 graphs.
10. Grid your answers correctly
The computer only grades what you have marked in
the bubbles. The space above the bubbles is just for
your convenience, and to help you do your bubbling
correctly.
Never mark more than one circle in a column or the
problem will automatically be marked wrong. You do
not need to use all four columns. If you don’t use a
column just leave it blank.
The symbols that you can grid in are the digits 0
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through 9, a decimal point, and a division symbol for fractions. Note that
there is no negative symbol. So answers to grid-ins cannot be negative.
Also, there are only four slots, so you can’t get an answer such as
52,326.
Sometimes there is more than one correct answer to a grid-in question.
Simply choose one of them to grid-in. Never try to fit more than one
answer into the grid.
If your answer is a whole number such as 2451 or a decimal that only
requires four or less slots such as 2.36, then simply enter the number
starting at any column. The two examples just written must be started in
the first column, but the number 16 can be entered starting in column 1,
2 or 3.
Note that there is no zero in column 1, so if your answer is 0 it must be
gridded into column 2, 3 or 4.
Fractions can be gridded in any form as long as there are enough slots.
The fraction 2/100 must be reduced to 1/50 simply because the first
representation won’t fit in the grid.
Fractions can also be converted to decimals before being gridded in. If a
decimal cannot fit in the grid, then you can simply truncate it to fit. But
you must use every slot in this case. For example, the decimal
.167777777… can be gridded as .167, but .16 or .17 would both be
marked wrong.
Instead of truncating decimals you can also round them. For example,
the decimal above could be gridded as .168. Truncating is preferred
because there is no thinking involved and you are less likely to make a
careless error.
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Here are three ways to grid in the number 8/9.
Never grid-in mixed numerals. If your answer is 2 ¼, and you grid in the
mixed numeral 2 ¼, then this will be read as 21/4 and will be marked
wrong. You must either grid in the decimal 2.25 or the improper fraction
9/4.
Here are two ways to grid in the mixed numeral 1 ½ correctly.
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PROBLEMS BY LEVEL AND TOPIC WITH
FULLY EXPLAINED SOLUTIONS
Note: The quickest solution will always be marked with an asterisk (*).
LEVEL 1: NUMBER THEORY
1. Which of the following numbers is less than 0.216?
(A) 0.2106
(B) 0.2161
(C) 0.2166
(D) 0.22
(E) 0.221
We can compare two decimals by looking at the first position where
they disagree. For example, 0.215 is less than 0.216 because 5 is less
than 6. If a digit is missing, there is a hidden 0 there. Thus 0.2 is also less
than 0.216 because 0.2 is the same as 0.200 and 0 is less than 1
(remember that we look at the first position where the decimals
disagree). Thus the answer here is choice (A) since 0 is less than 6.
* Quick Solution: Answers are given in increasing or decreasing order on
the SAT (in this problem they are given in increasing order). Therefore
choice (A) is the only reasonable answer.
Remark: The words “less than” would seem to indicate we should start
by looking at the smallest answer choice. In this case that is choice (A).
For more information, see Strategy 2 in “The 32 Most Effective SAT
Math Strategies.”
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2. What is the greatest positive integer that is a divisor of 10, 25,
and 45?
(A) 1
(B) 2
(C) 3
(D) 5
(E) 10
Beginner Method: Pull out your calculator. Since the question has the
word “greatest” in it, we will start with the greatest answer choice
which is choice (E), and we will divide each of the three numbers by 10.
Since 25 divided by 10 is 2.5 (not an integer), choice (E) is not the
answer. We next try choice (D). The divisions give us 2, 5 and 9
respectively. Since these are all integers, the answer is choice (D).
Note that the three given integers are all divisible by 1, but choice (A) is
not the answer because 5 is greater.
Here we have used Strategy 2 in “The 32 Most Effective SAT Math
Strategies.”
* Intermediate Method: As in the beginner method, we begin with the
greatest answer choice. Since 25 (as well as 45) does not end in a 0, it is
not divisible by 10. Since all three integers end in a 0 or a 5, they are all
divisible by 5. Thus, the answer is choice (D).
Advanced Method: We are being asked to find the greatest common
factor of 10, 25 and 45, which is 5, choice (D).
Finding the greatest common factor: Here are two ways to find the
greatest common factor of the given integers.
(1) List all factors of each integer and look for the biggest one they
have in common.
Factors of 10: {1, 2, 5 10}
Factors of 25: {1, 5, 25}
Factors of 45: {1, 3, 5, 9, 15, 45}
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Common Factors: {1, 5}
Thus, the greatest common factor is 5.
(2) Here is a more sophisticated method that is much quicker if the
given integers are large.
Step 1: Find the prime factorization of each number in the set.
10 = 2*5
25 = 5
2
45 = 3
2
*5
Step 2: Choose the lowest power of each prime that appears in all of the
factorizations. In this case, this is just 5.
Step 3: Multiply these numbers together to get the greatest common
factor. (In this case there is nothing to multiply since there is only one
prime factor that the three integers have in common.)
Remark: We can also write the above prime factorizations as follows:
10 = 2
1
3
0
5
1
25 = 2
0
3
0
5
2
45 = 2
0
3
2
5
1
It is easy to see in this form that the lowest power of 2 is 2
0
= 1, and
similarly the lowest power of 3 is 3
0
.
3. A positive integer is called a palindrome if it reads the same
forward as it does backward. For example, 2442 is a
palindrome. Which of the following integers is a palindrome?
(A) 1010
(B) 1011
(C) 2002
(D) 2020
(E) 2021
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* Begin by looking at choice (C). It reads the same forward and
backward. Therefore choice (C) is the answer.
Here we have used Strategy 1 in “The 32 Most Effective SAT Math
Strategies.”
4. Which of the following numbers is between
7
1
and
6
1
?
(A) 0.13
(B) 0.15
(C) 0.17
(D) 0.19
(E) 0.21
* Change the two fractions to decimals by dividing in your calculator
(decimals are much easier to compare than fractions). When you divide
1 by 7 you get about 0.1429. When you divide 1 by 6 you get about
0.1667. Since 0.15 is between these two the answer is choice (B).
For more information on this technique, see Strategy 15 in “The 32
Most Effective SAT Math Strategies.”
5. Which of the following numbers disproves the statement “A
number that is divisible by 4 and 8 is also divisible by 12”?
(A) 24
(B) 48
(C) 56
(D) 72
(E) 96
We want a number that is divisible by 4 and 8, but not by 12. Use your
calculator and begin with choice (C). When we divide 56 by 4, 8 and 12
we get 14, 7 and about 4.67. Since 14 and 7 are integers we see that 56
is divisible by 4 and 8. Since 4.67 is not an integer 56 is not divisible by
12. Thus, choice (C) is the answer.
Here we have used Strategy 1 in “The 32 Most Effective SAT Math
Strategies.”
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* Slight upgrade: Any integer which is divisible by 8 is automatically
divisible by 4. Thus, we need only check that 56 is divisible by 8 and that
56 is not divisible by 12.
6.
2
) 4 3 (
* Without a calculator: (3 + 4)
2
= 7
2
= 49.
Remark: Ideally, you should do the above computation in your head.
With a calculator: Type (3 + 4)^2 into your calculator. The output is 49.
7. Each of A, B, C, D and E are distinct numbers from the set
{2, 15, 25, 31, 34} such that A is prime, B is even, C and D are
multiples of 5, and A < E < B. What is E?
* Remember that a prime number is a positive integer with exactly 2
factors (1 and itself). Since A is prime, it is either 2 or 31. Since B is even
and greater than A it must be 34. Since C and D are multiples of 5 they
must be 15 and 25 (not necessarily in that order). So E must be 31.
Definitions: A prime number is a positive integer that has exactly two
factors (1 and itself). Here is a list of the first few primes:
2, 3, 5, 7, 11, 13, 17, 19, 23,…
Note that 1 is not prime. It only has one factor!
A composite number has more than two factors. Here is a list of the first
few composites:
4, 6, 8, 9, 10, 12, 14, 15, 16,…
8. Three consecutive integers are listed in increasing order. If their
sum is 732, what is the second integer in the list?
Beginner Method: Let us try some guesses for the second integer.
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2
nd
integer 1
st
integer 3
rd
integer Sum
200 199 201 600
250 249 251 750
240 239 241 720
245 244 246 735
244 243 245 732
Thus, the answer is 244.
Remark: You should use your calculator to compute these sums. This will
be quicker and you are less likely to make a careless error.
Here we have used Strategy 3 in “The 32 Most Effective SAT Math
Strategies.”
Intermediate Method: If we name the least integer x, then the second
and third integers are x + 1 and x + 2, respectively. So we have
x + (x + 1) + (x + 2) = 732
3x + 3 = 732
3x = 729
x = 243
The second integer is x + 1 = 244.
* Advanced Method: Simply divide 732 by 3 to get 244.
Remark for the advanced student: The following algebraic steps show
why the advanced method gives the correct solution.
x + (x + 1) + (x + 2) = 732
3x + 3 = 732
3(x + 1) = 732
x + 1 = 244.
Note that the last two steps show that x + 1 = 732/3.
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A F T E R W O R D
YOUR ROAD
TO SUCCESS
ongratulations! By practicing the problems in this book you
have given yourself a significant boost to your SAT math score. Go ahead
and take a practice SAT. The math score you get should be much higher
than the score you received on your PSAT.
What should you do to get your score even higher? Good news!
You can use this book over and over again to continue to increase your
score – right up to an 800. All you need to do is change the problems
you are focusing on.
If you are currently scoring less than a 400 you should go back
and focus on those Level 1 problems.
If you are between a 400 and 500 you should focus on Level 2
problems, but do all the Level 1 problems and some Level 3 problems as
well.
If you are between a 500 and 600, then focus on Level 2 and 3
problems, and throw in a few Level 4 problems every now and then.
If you are between a 600 and 700, then the Level 4 problems are
really important. Go ahead and work on all of them, but do some Level 2
and 3 problems as well.
Finally, if you are scoring in the 700s, it is time to focus primarily
on Level 4 and 5 problems.
These are just general guidelines, and you may want to fine tune
this a bit by analyzing each of the four subject areas separately. For
example, if you are scoring between a 600 and 700 but you are not
getting any Level 4 Geometry problems correct, then shift your focus to
Level 3 Geometry problems for a little while. Come back to the Level 4
problems after you become a bit more proficient in Level 3 Geometry.
Similarly, if you are breezing through the Level 4 Number Theory
Problems, then start focusing on Level 5 Number Theory. On your next
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practice test you can try those last few Number Theory questions at the
end of each math section.
Upon your next reading, try to solve each problem that you
attempt in up to four different ways
Using an SAT specific math strategy.
The quickest way you can think of.
The way you would do it in school.
The easiest way for you.
Remember – the actual answer is not very important. What is
important is to learn as many techniques as possible. This is the best
way to simultaneously increase your current score, and increase your
level of mathematical maturity.
Keep doing problems from this book for ten to twenty minutes
each day right up until two days before your SAT. Mark off the ones you
get wrong and attempt them over and over again each week until you
can get them right on your own.
I really want to thank you for putting your trust in me and my
materials, and I want to assure you that you have made excellent use of
your time by studying with this book. I wish you the best of luck on the
SAT, on getting into your choice college, and in life.
Steve Warner, Ph.D.
steve@SATPrepGet800.com
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203
About the Author
Steve Warner, a New York native, earned his Ph.D. at Rutgers University in Pure
Mathematics in May, 2001. While a graduate student, Dr. Warner won the TA
Teaching Excellence Award.
After Rutgers, Dr. Warner joined the Penn
State Mathematics Department as an
Assistant Professor. In September, 2002,
Dr. Warner returned to New York to
accept an Assistant Professor position at
Hofstra University. By September 2007, Dr.
Warner had received tenure and was
promoted to Associate Professor. He has
taught undergraduate and graduate
courses in Precalculus, Calculus, Linear
Algebra, Differential Equations,
Mathematical Logic, Set Theory and Abstract Algebra.
Over that time, Dr. Warner participated in a five year NSF grant, “The MSTP
Project,” to study and improve mathematics and science curriculum in poorly
performing junior high schools. He also published several articles in scholarly
journals, specifically on Mathematical Logic.
Dr. Warner has over 15 years of experience in general math tutoring and over
10 years of experience in SAT math tutoring. He has tutored students both
individually and in group settings.
In February, 2010 Dr. Warner released his first SAT prep book “The 32 Most
Effective SAT Math Strategies.” The second edition of this book was released in
January, 2011.
Currently Dr. Warner lives in Staten Island with his two cats, Achilles and Odin.
Since the age of 4, Dr. Warner has enjoyed playing the piano—especially
compositions of Chopin as well as writing his own music. He also maintains his
physical fitness through weightlifting.
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204
BOOKS BY DR. STEVE WARNER
CONNECT WITH DR. STEVE WARNER
Legal Notice
This book is copyright 2012 with all rights reserved. It is illegal to copy,
distribute, or create derivative works from this book in whole or in part
or to contribute to the copying, distribution, or creating of derivative
works of this book.
iii
A Proven Roadmap to
Your First-Choice College
Steve Warner, Ph.D.
© 2012, All Rights Reserved
SATPrepGet800.com © 2013
iv
This book is dedicated to all my students over the past
12 years, I have learned just as much from all of you as
you have learned from me.
I would also like to acknowledge Larry Ronaldson and Robert
Folatico, thank you for introducing me to the rewarding field of
SAT tutoring.
BOOKS BY DR. STEVE WARNER FOR COLLEGE BOUND STUDENTS
28 SAT Math Lessons to Improve Your Score in One Month
Beginner Course
Intermediate Course
Advanced Course
320 SAT Math Problems Arranged by Topic and Difficulty Level
SAT Prep Book of Advanced Math Problems
The 32 Most Effective SAT Math Strategies
SAT Prep Official Study Guide Math Companion
ACT Prep Red Book – 320 ACT Math Problems with Solutions
CONNECT WITH DR. STEVE WARNER
v
Table of Contents
Introduction: The Proper Way to Prepare 7
1. The magical mixture for success 7
2. Practice problems of the appropriate level 9
3. Practice in small amounts over a long period of time 9
4. Redo the problems you get wrong over and over and
over until you get them right 10
5. Check your answers properly 10
6. Guess when appropriate 11
7. Pace yourself 11
8. Attempt the right number of questions 12
9. Use your calculator wisely 13
10. Grid your answers correctly 14
Problems by Level and Topic with Fully Explained Solutions 17
Level 1: Number Theory 17
Level 1: Algebra and Functions 23
Level 1: Geometry 28
Level 1: Probability and Statistics 34
Level 2: Number Theory 40
Level 2: Algebra and Functions 46
Level 2: Geometry 52
Level 2: Probability and Statistics 58
Level 3: Number Theory 64
Level 3: Algebra and Functions 72
Level 3: Geometry 79
Level 3: Probability and Statistics 86
Level 4: Number Theory 92
Level 4: Algebra and Functions 99
Level 4: Geometry 104
Level 4: Probability and Statistics 110
Level 5: Number Theory 117
Level 5: Algebra and Functions 125
Level 5: Geometry 133
Level 5: Probability and Statistics 142
vi
Supplemental Problems – Questions 149
Level 1: Number Theory 149
Level 1: Algebra and Functions 150
Level 1: Geometry 152
Level 1: Probability and Statistics 155
Level 2: Number Theory 156
Level 2: Algebra and Functions 158
Level 2: Geometry 160
Level 2: Probability and Statistics 163
Level 3: Number Theory 165
Level 3: Algebra and Functions 166
Level 3: Geometry 169
Level 3: Probability and Statistics 172
Level 4: Number Theory 174
Level 4: Algebra and Functions 176
Level 4: Geometry 178
Level 4: Probability and Statistics 181
Level 5: Number Theory 183
Level 5: Algebra and Functions 185
Level 5: Geometry 187
Level 5: Probability and Statistics 190
Answers to Supplemental Problems 194
Afterword: Your Road to Success 201
About the Author 203
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I N T R O D U C T I O N
THE PROPER WAY TO PREPARE
here are many ways that a student can prepare for the SAT.
But not all preparation is created equal. I always teach my students the
methods that will give them the maximum result with the minimum
amount of effort.
In “The 32 Most Effective SAT Math Strategies” I emphasize the
most important techniques for this particular test. That book contains
115 problems that are perfect for implementing the various strategies
discussed there. In fact, using that book alone is enough to significantly
boost anyone’s SAT math score.
The book you are now reading is also self-contained. Each problem
was carefully created to ensure that you are making the most effective
use of your time while preparing for the SAT. By grouping the problems
given here by level and topic I have ensured that you can focus on the
types of problems that will be most effective to improving your score.
1. The magical mixture for success
A combination of three components will maximize your SAT math score
with the least amount of effort.
Learning test taking strategies that are specific to the SAT.
Practicing SAT problems for a small amount of time each day for
about three months before the SAT.
Taking about four practice tests before test day to make sure
you are applying the strategies effectively under timed
conditions.
I will discuss each of these three components in a bit more detail.
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Strategy: The more SAT specific strategies that you know the better off
you will be. All the strategies you need to know are in “The 32 Most
Effective SAT Math Strategies,” as well as 115 problems to practice
implementing these strategies. Note that it is not enough to know these
strategies. You must practice using them on SAT problems as often as
possible.
Practice: The book you are now reading is ideal for accomplishing this
task. The problems given in this book are more than enough to vastly
improve your current SAT math score. All you need to do is work on
these problems for about ten to twenty minutes each day over a period
of three to four months and the final result will far exceed your
expectations.
Let me further break this component into two subcomponents – topic
and level.
Topic: You want to practice each of the four general math topics
given on the SAT and improve in each independently. The four topics are
Number Theory, Algebra and Functions, Geometry, and Probability and
Statistics. The problem sets in this book are broken into these four
topics.
Level: You will make the best use of your time by primarily
practicing problems that are at and slightly above your current ability
level. For example, if you are struggling with Level 2 Geometry problems,
then it makes no sense at all to practice Level 5 Geometry problems.
Keep working on Level 2 until you are comfortable, and then slowly
move up to Level 3. Maybe you should never attempt those Level 5
problems. You can get an exceptional score without them (higher than
700).
Tests: You want to take about four practice tests before test day to
make sure that you are implementing strategies correctly and using your
time wisely under pressure. For this task you should use the second
edition of “The Official SAT Study Guide” by the College Board. Take one
test every few weeks to make sure that you are implementing all the
strategies you have learned correctly under timed conditions. Note that
only the second edition has three actual SATs.
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2. Practice problems of the appropriate level
Roughly speaking about one third of the math problems on the SAT are
easy, one third are medium, and one third are hard. If you answer two
thirds of the math questions on the SAT correctly, then your score will
be approximately a 600 (out of 800). That’s right—you can get about a
600 on the math portion of the SAT without answering a single hard
question.
Keep track of your current ability level so that you know the types of
problems you should focus on. If you are currently scoring around a 400
on your practice tests, then you should be focusing primarily on Level 1,
2, and 3 problems. You can easily raise your score 100 points without
having to practice a single hard problem.
If you are currently scoring about a 500, then your primary focus should
be Level 2 and 3, but you should also do some Level 1 and 4 problems.
If you are scoring around a 600, you should be focusing on Level 2, 3,
and 4 problems, but you should do some Level 1 and 5 problems as well.
Those of you at the 700 level really need to focus on those Level 4 and 5
problems.
If you really want to refine your studying, then you should keep track of
your ability level in each of the four major categories of problems:
Number Theory
Algebra and Functions
Probability, Statistics and Data Analysis
Geometry
For example, many students have trouble with very easy geometry
problems, even though they can do more difficult number theory
problems. This type of student may want to focus on Level 1, 2, and 3
geometry questions, but Level 3 and 4 number theory questions.
3. Practice in small amounts over a long period of time
Ideally you want to practice doing SAT math problems ten to twenty
minutes each day beginning at least 3 months before the exam. You will
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retain much more of what you study if you study in short bursts than if
you try to tackle everything at once.
The only exception is on a day you do a practice test. You should do at
least four practice tests before you take the SAT. Ideally you should do
your practice tests on a Saturday or Sunday morning. At first you can do
just the 3 math sections. The last one or two times you take a practice
test you should do the whole test in one sitting. As tedious as this is, it
will prepare you for the amount of endurance that it will take to get
through this exam.
So try to choose about a twenty minute block of time that you will
dedicate to SAT math every night. Make it a habit. The results are well
worth this small time commitment.
4. Redo the problems you get wrong over and over and
over until you get them right
If you get a problem wrong, and never attempt the problem again, then
it is extremely unlikely that you will get a similar problem correct if it
appears on the SAT.
Most students will read an explanation of the solution, or have someone
explain it to them, and then never look at the problem again. This is not
how you optimize your SAT score. To be sure that you will get a similar
problem correct on the SAT, you must get the problem correct before
the SAT—and without actually remembering the problem.
This means that after getting a problem incorrect, you should go over
and understand why you got it wrong, wait at least a few days, then
attempt the same problem again. If you get it right you can cross it off
your list of problems to review. If you get it wrong, keep revisiting it
every few days until you get it right. Your score does not improve by
getting problems correct. Your score improves when you learn from
your mistakes.
5. Check your answers properly
When you go back to check your earlier answers for careless errors do
not simply look over your work to try to catch a mistake. This is usually a
waste of time. Always redo the problem without looking at any of your
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11
previous work. Ideally, you want to use a different method than you
used the first time.
For example, if you solved the problem by picking numbers the first
time, try to solve it algebraically the second time, or at the very least
pick different numbers. If you don’t know, or are not comfortable with a
different method, then use the same method, but do the problem from
the beginning and do not look at your original solution. If your two
answers don’t match up, then you know that this a problem you need to
spend a little more time on to figure out where your error is.
This may seem time consuming, but that’s ok. It is better to spend more
time checking over a few problems than to rush through a lot of
problems and repeat the same mistakes.
6. Guess when appropriate
Answering a multiple choice question wrong will result in a 1/4 point
penalty. This is to discourage random guessing. If you have no idea how
to do a problem, no intuition as to what the correct answer might be,
and you can’t even eliminate a single answer choice, then DO NOT just
take a guess. Omit the question and move on.
If, however, you can eliminate even one answer choice, you should take
a guess from the remaining four. You should of course eliminate as many
choices as you can before you take your guess.
You are not penalized for getting a grid-in question wrong. Therefore
you should always guess on grid-in questions that you don’t know. Never
leave any of these blank. If you have an idea of how large of a number
the answer should be, then take a reasonable guess. If not, then just
guess anything—don’t think too hard—just put in a number.
7. Pace yourself
Do not waste your time on a question that is too hard or will take too
long. After you’ve been working on a question for about 1 minute you
need to make a decision. If you understand the question and think that
you can get the answer in another 30 seconds or so, continue to work on
the problem. If you still don’t know how to do the problem or you are
using a technique that is going to take a long time, mark it off and come
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12
back to it later if you have time.
If you have eliminated at least one answer choice, or it is a grid-in, feel
free to take a guess. But you still want to leave open the possibility of
coming back to it later. Remember that every problem is worth the same
amount. Don’t sacrifice problems that you may be able to do by getting
hung up on a problem that is too hard for you.
8. Attempt the right number of questions
There are three math sections on the SAT. They can appear in any order.
There is a 20 question multiple choice section, a 16 question multiple
choice section, and an 18 question section that has 8 multiple choice
questions and 10 grid-ins.
Let us call these sections A, B, and C, respectively. You should first make
sure that you know what you got on your last SAT practice test, actual
SAT, or actual PSAT (whichever you took last). What follows is a general
goal you should go for when taking the exam.
Score Section A Section B Section C
(Multiple
choice)
Section C
(Grid-in)
< 330 7/20 6/16 2/8 2/10
330 – 370 10/20 8/16 3/8 3/10
380 – 430 12/20 10/16 4/8 4/10
440 – 490 14/20 11/16 5/8 6/10
500 – 550 16/20 12/16 6/8 8/10
560 – 620 18/20 15/16 7/8 9/10
630 – 800 20/20 16/16 8/8 10/10
For example, a student with a current score of 450 should attempt the
first 14 questions from section A, the first 11 questions from section B,
the first 5 multiple choice questions from section C, and the first 6 gridins from section C.
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13
This is just a general guideline. Of course it can be fine-tuned. As a
simple example, if you are particularly strong at number theory
problems, but very weak at geometry problems, then you may want to
try every number theory problem no matter where it appears, and you
may want to reduce the number of geometry problems you attempt.
9. Use your calculator wisely.
It is recommended that you use a TI-84 or comparable calculator for the
SAT. It is important that you are comfortable with your calculator on test
day, so make sure that you are consistently practicing with the calculator
you plan to use. Make sure that your calculator has fresh batteries the
day of the test. Nobody will supply a calculator for you if yours dies.
Below are the most important things you should practice on your
graphing calculator.
(1) Practice entering complicated computations in a single step, and
know when to insert parentheses. In general, there are 4 instances when
you should use parentheses in your calculator.
Around numerators of fractions
Around denominators of fractions
Around exponents
Whenever you actually see parentheses in the expression
Examples:
We will substitute a 5 in for x in each of the following examples.
Expression Calculator computation
11 2
3 7
x
x
(7*5 + 3)/(2*5 – 11)
9 2
) 8 3 (
x
x
(3*5 – 8)^(2*5 – 9)
(2) Clear the screen before using it in a new problem. The big screen
allows you to check over your computations easily.
(3) Press the ANS button (2
nd
(-) ) to use your last answer in the next
computation.
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14
(4) Press 2
nd
ENTER to bring up your last computation for editing. This is
especially useful when you are plugging in answer choices, or guessing
and checking.
(5) You can press 2
nd
ENTER over and over again to cycle backwards
through all the computations you have ever done.
(6) Know where the ,
, and ^ buttons are so you can reach them
quickly.
(7) Change a decimal to a fraction by pressing MATH ENTER ENTER.
(8) Press the MATH button - in the first menu that appears you can take
cube roots and nth roots for any n. Scroll right to PRB and you have nPr
and nCr to compute permutations and combinations very quickly.
The following items are less important but can be useful.
(9) Press the Y= button to enter a function, and then hit ZOOM 6 to
graph it in a standard window.
(10) Practice using the WINDOW button to adjust the viewing window of
your graph.
(11) Practice using the TRACE button to move along the graph and look
at some of the points plotted.
(12) Pressing 2nd TRACE (which is really CALC) will bring up a menu of
useful items. For example selecting ZERO will tell you where the graph
hits the x-axis, or equivalently where the function is zero. Selecting
MINIMUM or MAXIMUM can find the vertex of a parabola. Selecting
INTERSECT will find the point of intersection of 2 graphs.
10. Grid your answers correctly
The computer only grades what you have marked in
the bubbles. The space above the bubbles is just for
your convenience, and to help you do your bubbling
correctly.
Never mark more than one circle in a column or the
problem will automatically be marked wrong. You do
not need to use all four columns. If you don’t use a
column just leave it blank.
The symbols that you can grid in are the digits 0
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15
through 9, a decimal point, and a division symbol for fractions. Note that
there is no negative symbol. So answers to grid-ins cannot be negative.
Also, there are only four slots, so you can’t get an answer such as
52,326.
Sometimes there is more than one correct answer to a grid-in question.
Simply choose one of them to grid-in. Never try to fit more than one
answer into the grid.
If your answer is a whole number such as 2451 or a decimal that only
requires four or less slots such as 2.36, then simply enter the number
starting at any column. The two examples just written must be started in
the first column, but the number 16 can be entered starting in column 1,
2 or 3.
Note that there is no zero in column 1, so if your answer is 0 it must be
gridded into column 2, 3 or 4.
Fractions can be gridded in any form as long as there are enough slots.
The fraction 2/100 must be reduced to 1/50 simply because the first
representation won’t fit in the grid.
Fractions can also be converted to decimals before being gridded in. If a
decimal cannot fit in the grid, then you can simply truncate it to fit. But
you must use every slot in this case. For example, the decimal
.167777777… can be gridded as .167, but .16 or .17 would both be
marked wrong.
Instead of truncating decimals you can also round them. For example,
the decimal above could be gridded as .168. Truncating is preferred
because there is no thinking involved and you are less likely to make a
careless error.
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Here are three ways to grid in the number 8/9.
Never grid-in mixed numerals. If your answer is 2 ¼, and you grid in the
mixed numeral 2 ¼, then this will be read as 21/4 and will be marked
wrong. You must either grid in the decimal 2.25 or the improper fraction
9/4.
Here are two ways to grid in the mixed numeral 1 ½ correctly.
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PROBLEMS BY LEVEL AND TOPIC WITH
FULLY EXPLAINED SOLUTIONS
Note: The quickest solution will always be marked with an asterisk (*).
LEVEL 1: NUMBER THEORY
1. Which of the following numbers is less than 0.216?
(A) 0.2106
(B) 0.2161
(C) 0.2166
(D) 0.22
(E) 0.221
We can compare two decimals by looking at the first position where
they disagree. For example, 0.215 is less than 0.216 because 5 is less
than 6. If a digit is missing, there is a hidden 0 there. Thus 0.2 is also less
than 0.216 because 0.2 is the same as 0.200 and 0 is less than 1
(remember that we look at the first position where the decimals
disagree). Thus the answer here is choice (A) since 0 is less than 6.
* Quick Solution: Answers are given in increasing or decreasing order on
the SAT (in this problem they are given in increasing order). Therefore
choice (A) is the only reasonable answer.
Remark: The words “less than” would seem to indicate we should start
by looking at the smallest answer choice. In this case that is choice (A).
For more information, see Strategy 2 in “The 32 Most Effective SAT
Math Strategies.”
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2. What is the greatest positive integer that is a divisor of 10, 25,
and 45?
(A) 1
(B) 2
(C) 3
(D) 5
(E) 10
Beginner Method: Pull out your calculator. Since the question has the
word “greatest” in it, we will start with the greatest answer choice
which is choice (E), and we will divide each of the three numbers by 10.
Since 25 divided by 10 is 2.5 (not an integer), choice (E) is not the
answer. We next try choice (D). The divisions give us 2, 5 and 9
respectively. Since these are all integers, the answer is choice (D).
Note that the three given integers are all divisible by 1, but choice (A) is
not the answer because 5 is greater.
Here we have used Strategy 2 in “The 32 Most Effective SAT Math
Strategies.”
* Intermediate Method: As in the beginner method, we begin with the
greatest answer choice. Since 25 (as well as 45) does not end in a 0, it is
not divisible by 10. Since all three integers end in a 0 or a 5, they are all
divisible by 5. Thus, the answer is choice (D).
Advanced Method: We are being asked to find the greatest common
factor of 10, 25 and 45, which is 5, choice (D).
Finding the greatest common factor: Here are two ways to find the
greatest common factor of the given integers.
(1) List all factors of each integer and look for the biggest one they
have in common.
Factors of 10: {1, 2, 5 10}
Factors of 25: {1, 5, 25}
Factors of 45: {1, 3, 5, 9, 15, 45}
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Common Factors: {1, 5}
Thus, the greatest common factor is 5.
(2) Here is a more sophisticated method that is much quicker if the
given integers are large.
Step 1: Find the prime factorization of each number in the set.
10 = 2*5
25 = 5
2
45 = 3
2
*5
Step 2: Choose the lowest power of each prime that appears in all of the
factorizations. In this case, this is just 5.
Step 3: Multiply these numbers together to get the greatest common
factor. (In this case there is nothing to multiply since there is only one
prime factor that the three integers have in common.)
Remark: We can also write the above prime factorizations as follows:
10 = 2
1
3
0
5
1
25 = 2
0
3
0
5
2
45 = 2
0
3
2
5
1
It is easy to see in this form that the lowest power of 2 is 2
0
= 1, and
similarly the lowest power of 3 is 3
0
.
3. A positive integer is called a palindrome if it reads the same
forward as it does backward. For example, 2442 is a
palindrome. Which of the following integers is a palindrome?
(A) 1010
(B) 1011
(C) 2002
(D) 2020
(E) 2021
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* Begin by looking at choice (C). It reads the same forward and
backward. Therefore choice (C) is the answer.
Here we have used Strategy 1 in “The 32 Most Effective SAT Math
Strategies.”
4. Which of the following numbers is between
7
1
and
6
1
?
(A) 0.13
(B) 0.15
(C) 0.17
(D) 0.19
(E) 0.21
* Change the two fractions to decimals by dividing in your calculator
(decimals are much easier to compare than fractions). When you divide
1 by 7 you get about 0.1429. When you divide 1 by 6 you get about
0.1667. Since 0.15 is between these two the answer is choice (B).
For more information on this technique, see Strategy 15 in “The 32
Most Effective SAT Math Strategies.”
5. Which of the following numbers disproves the statement “A
number that is divisible by 4 and 8 is also divisible by 12”?
(A) 24
(B) 48
(C) 56
(D) 72
(E) 96
We want a number that is divisible by 4 and 8, but not by 12. Use your
calculator and begin with choice (C). When we divide 56 by 4, 8 and 12
we get 14, 7 and about 4.67. Since 14 and 7 are integers we see that 56
is divisible by 4 and 8. Since 4.67 is not an integer 56 is not divisible by
12. Thus, choice (C) is the answer.
Here we have used Strategy 1 in “The 32 Most Effective SAT Math
Strategies.”
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* Slight upgrade: Any integer which is divisible by 8 is automatically
divisible by 4. Thus, we need only check that 56 is divisible by 8 and that
56 is not divisible by 12.
6.
2
) 4 3 (
* Without a calculator: (3 + 4)
2
= 7
2
= 49.
Remark: Ideally, you should do the above computation in your head.
With a calculator: Type (3 + 4)^2 into your calculator. The output is 49.
7. Each of A, B, C, D and E are distinct numbers from the set
{2, 15, 25, 31, 34} such that A is prime, B is even, C and D are
multiples of 5, and A < E < B. What is E?
* Remember that a prime number is a positive integer with exactly 2
factors (1 and itself). Since A is prime, it is either 2 or 31. Since B is even
and greater than A it must be 34. Since C and D are multiples of 5 they
must be 15 and 25 (not necessarily in that order). So E must be 31.
Definitions: A prime number is a positive integer that has exactly two
factors (1 and itself). Here is a list of the first few primes:
2, 3, 5, 7, 11, 13, 17, 19, 23,…
Note that 1 is not prime. It only has one factor!
A composite number has more than two factors. Here is a list of the first
few composites:
4, 6, 8, 9, 10, 12, 14, 15, 16,…
8. Three consecutive integers are listed in increasing order. If their
sum is 732, what is the second integer in the list?
Beginner Method: Let us try some guesses for the second integer.
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2
nd
integer 1
st
integer 3
rd
integer Sum
200 199 201 600
250 249 251 750
240 239 241 720
245 244 246 735
244 243 245 732
Thus, the answer is 244.
Remark: You should use your calculator to compute these sums. This will
be quicker and you are less likely to make a careless error.
Here we have used Strategy 3 in “The 32 Most Effective SAT Math
Strategies.”
Intermediate Method: If we name the least integer x, then the second
and third integers are x + 1 and x + 2, respectively. So we have
x + (x + 1) + (x + 2) = 732
3x + 3 = 732
3x = 729
x = 243
The second integer is x + 1 = 244.
* Advanced Method: Simply divide 732 by 3 to get 244.
Remark for the advanced student: The following algebraic steps show
why the advanced method gives the correct solution.
x + (x + 1) + (x + 2) = 732
3x + 3 = 732
3(x + 1) = 732
x + 1 = 244.
Note that the last two steps show that x + 1 = 732/3.
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A F T E R W O R D
YOUR ROAD
TO SUCCESS
ongratulations! By practicing the problems in this book you
have given yourself a significant boost to your SAT math score. Go ahead
and take a practice SAT. The math score you get should be much higher
than the score you received on your PSAT.
What should you do to get your score even higher? Good news!
You can use this book over and over again to continue to increase your
score – right up to an 800. All you need to do is change the problems
you are focusing on.
If you are currently scoring less than a 400 you should go back
and focus on those Level 1 problems.
If you are between a 400 and 500 you should focus on Level 2
problems, but do all the Level 1 problems and some Level 3 problems as
well.
If you are between a 500 and 600, then focus on Level 2 and 3
problems, and throw in a few Level 4 problems every now and then.
If you are between a 600 and 700, then the Level 4 problems are
really important. Go ahead and work on all of them, but do some Level 2
and 3 problems as well.
Finally, if you are scoring in the 700s, it is time to focus primarily
on Level 4 and 5 problems.
These are just general guidelines, and you may want to fine tune
this a bit by analyzing each of the four subject areas separately. For
example, if you are scoring between a 600 and 700 but you are not
getting any Level 4 Geometry problems correct, then shift your focus to
Level 3 Geometry problems for a little while. Come back to the Level 4
problems after you become a bit more proficient in Level 3 Geometry.
Similarly, if you are breezing through the Level 4 Number Theory
Problems, then start focusing on Level 5 Number Theory. On your next
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practice test you can try those last few Number Theory questions at the
end of each math section.
Upon your next reading, try to solve each problem that you
attempt in up to four different ways
Using an SAT specific math strategy.
The quickest way you can think of.
The way you would do it in school.
The easiest way for you.
Remember – the actual answer is not very important. What is
important is to learn as many techniques as possible. This is the best
way to simultaneously increase your current score, and increase your
level of mathematical maturity.
Keep doing problems from this book for ten to twenty minutes
each day right up until two days before your SAT. Mark off the ones you
get wrong and attempt them over and over again each week until you
can get them right on your own.
I really want to thank you for putting your trust in me and my
materials, and I want to assure you that you have made excellent use of
your time by studying with this book. I wish you the best of luck on the
SAT, on getting into your choice college, and in life.
Steve Warner, Ph.D.
steve@SATPrepGet800.com
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About the Author
Steve Warner, a New York native, earned his Ph.D. at Rutgers University in Pure
Mathematics in May, 2001. While a graduate student, Dr. Warner won the TA
Teaching Excellence Award.
After Rutgers, Dr. Warner joined the Penn
State Mathematics Department as an
Assistant Professor. In September, 2002,
Dr. Warner returned to New York to
accept an Assistant Professor position at
Hofstra University. By September 2007, Dr.
Warner had received tenure and was
promoted to Associate Professor. He has
taught undergraduate and graduate
courses in Precalculus, Calculus, Linear
Algebra, Differential Equations,
Mathematical Logic, Set Theory and Abstract Algebra.
Over that time, Dr. Warner participated in a five year NSF grant, “The MSTP
Project,” to study and improve mathematics and science curriculum in poorly
performing junior high schools. He also published several articles in scholarly
journals, specifically on Mathematical Logic.
Dr. Warner has over 15 years of experience in general math tutoring and over
10 years of experience in SAT math tutoring. He has tutored students both
individually and in group settings.
In February, 2010 Dr. Warner released his first SAT prep book “The 32 Most
Effective SAT Math Strategies.” The second edition of this book was released in
January, 2011.
Currently Dr. Warner lives in Staten Island with his two cats, Achilles and Odin.
Since the age of 4, Dr. Warner has enjoyed playing the piano—especially
compositions of Chopin as well as writing his own music. He also maintains his
physical fitness through weightlifting.
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BOOKS BY DR. STEVE WARNER
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