GMAT Question of the Day - Daily to your Mailbox; hard ones only

 It is currently 19 Jan 2019, 02:53

GMAT Club Daily Prep

Thank you for using the timer - this advanced tool can estimate your performance and suggest more practice questions. We have subscribed you to Daily Prep Questions via email.

Customized
for You

we will pick new questions that match your level based on your Timer History

Track

every week, we’ll send you an estimated GMAT score based on your performance

Practice
Pays

we will pick new questions that match your level based on your Timer History

Events & Promotions

Events & Promotions in January
PrevNext
SuMoTuWeThFrSa
303112345
6789101112
13141516171819
20212223242526
272829303112
Open Detailed Calendar
• Free GMAT Strategy Webinar

January 19, 2019

January 19, 2019

07:00 AM PST

09:00 AM PST

Aiming to score 760+? Attend this FREE session to learn how to Define your GMAT Strategy, Create your Study Plan and Master the Core Skills to excel on the GMAT.
• FREE Quant Workshop by e-GMAT!

January 20, 2019

January 20, 2019

07:00 AM PST

07:00 AM PST

Get personalized insights on how to achieve your Target Quant Score.

Math Revolution Approach (PS)

 new topic post reply Question banks Downloads My Bookmarks Reviews Important topics
Author Message
Math Revolution GMAT Instructor
Joined: 16 Aug 2015
Posts: 6815
GMAT 1: 760 Q51 V42
GPA: 3.82
Re: Math Revolution Approach (PS)  [#permalink]

Show Tags

03 Jul 2016, 16:31
If (1+x)y=y, which of the following must be true?
A. x=-1 or y=0
B. x=0 or y=0
C. x=1 or y=1
D. x=-1 or y=-1
E. x=0 or y=1

From y+xy=y, we get xy=0. Hence, the correct answer is B.
_________________

MathRevolution: Finish GMAT Quant Section with 10 minutes to spare
The one-and-only World’s First Variable Approach for DS and IVY Approach for PS with ease, speed and accuracy.
"Only \$149 for 3 month Online Course"
"Free Resources-30 day online access & Diagnostic Test"
"Unlimited Access to over 120 free video lessons - try it yourself"

Math Revolution GMAT Instructor
Joined: 16 Aug 2015
Posts: 6815
GMAT 1: 760 Q51 V42
GPA: 3.82
Re: Math Revolution Approach (PS)  [#permalink]

Show Tags

04 Jul 2016, 22:40
A(n+1)=1+(1/A(n)) and A(1)=1. What is the value of A(5)?

A. 2
B. 3/2
C. 5/3
D. 8/5
E. 13/8

Ans: If we substitute directly, the answer comes out to be D.
_________________

MathRevolution: Finish GMAT Quant Section with 10 minutes to spare
The one-and-only World’s First Variable Approach for DS and IVY Approach for PS with ease, speed and accuracy.
"Only \$149 for 3 month Online Course"
"Free Resources-30 day online access & Diagnostic Test"
"Unlimited Access to over 120 free video lessons - try it yourself"

Math Revolution GMAT Instructor
Joined: 16 Aug 2015
Posts: 6815
GMAT 1: 760 Q51 V42
GPA: 3.82
Re: Math Revolution Approach (PS)  [#permalink]

Show Tags

05 Jul 2016, 20:12
What is the units digit of 3^66?
A. 1
B. 3
C. 5
D. 7
E. 9

ANS: From 3^1=3, 3^2=9, 3^3=27, 3^4=81, the unit digit repeats in 3-->9-->7-->1-->3. Then, from 3^66=3^(4(16)+2), the unit digt is same as that of ^2. Hence, the answer is 9 and the correct answer choice is E.
_________________

MathRevolution: Finish GMAT Quant Section with 10 minutes to spare
The one-and-only World’s First Variable Approach for DS and IVY Approach for PS with ease, speed and accuracy.
"Only \$149 for 3 month Online Course"
"Free Resources-30 day online access & Diagnostic Test"
"Unlimited Access to over 120 free video lessons - try it yourself"

Math Revolution GMAT Instructor
Joined: 16 Aug 2015
Posts: 6815
GMAT 1: 760 Q51 V42
GPA: 3.82
Re: Math Revolution Approach (PS)  [#permalink]

Show Tags

06 Jul 2016, 15:52
Which of the following is closest to (10^19-10^3)/(10^17+1)?
A. 0.01
B. 0.1
C. 0.2
D. 1
E. 10

ANS: We get (10^17-10^3)/(10^17+1)≒(10^19)/(10^17)=1/100=0.01. Hence, the correct answer is A.
_________________

MathRevolution: Finish GMAT Quant Section with 10 minutes to spare
The one-and-only World’s First Variable Approach for DS and IVY Approach for PS with ease, speed and accuracy.
"Only \$149 for 3 month Online Course"
"Free Resources-30 day online access & Diagnostic Test"
"Unlimited Access to over 120 free video lessons - try it yourself"

Math Revolution GMAT Instructor
Joined: 16 Aug 2015
Posts: 6815
GMAT 1: 760 Q51 V42
GPA: 3.82
Re: Math Revolution Approach (PS)  [#permalink]

Show Tags

08 Jul 2016, 20:41
Which of the following is closest to (10!-9!)/(10!+9!)?
A. 0.01
B. 0.1
C. 0.2
D. 1
E. 10

ANS: (10!-9!)/(10!+9!)=(10-1)9!/(10+1)9!≒9/11=1. Hence, the correct answer is D
_________________

MathRevolution: Finish GMAT Quant Section with 10 minutes to spare
The one-and-only World’s First Variable Approach for DS and IVY Approach for PS with ease, speed and accuracy.
"Only \$149 for 3 month Online Course"
"Free Resources-30 day online access & Diagnostic Test"
"Unlimited Access to over 120 free video lessons - try it yourself"

Math Revolution GMAT Instructor
Joined: 16 Aug 2015
Posts: 6815
GMAT 1: 760 Q51 V42
GPA: 3.82
Re: Math Revolution Approach (PS)  [#permalink]

Show Tags

11 Jul 2016, 17:27
What is the scope including 1/21+1/12+1/13+......+1/30?
A 1/6~1/5
B. 1/5~1/4
C. 1/4~1/3
D. 1/3~1/2
E. 1/2~1

ANS: The sum of sequence is determined by the first and the last number. So, 1/3=10/30<1/21+1/12+1/13+......+1/30<10/21<10/20=1/2. The correct answer is D
_________________

MathRevolution: Finish GMAT Quant Section with 10 minutes to spare
The one-and-only World’s First Variable Approach for DS and IVY Approach for PS with ease, speed and accuracy.
"Only \$149 for 3 month Online Course"
"Free Resources-30 day online access & Diagnostic Test"
"Unlimited Access to over 120 free video lessons - try it yourself"

Math Revolution GMAT Instructor
Joined: 16 Aug 2015
Posts: 6815
GMAT 1: 760 Q51 V42
GPA: 3.82
Re: Math Revolution Approach (PS)  [#permalink]

Show Tags

12 Jul 2016, 17:58
8√4n=(4√2)^8, n=?
A. 4^8
B. 4^10
C. 4^12
D. 4^16
E. 4^32

ANS: D
_________________

MathRevolution: Finish GMAT Quant Section with 10 minutes to spare
The one-and-only World’s First Variable Approach for DS and IVY Approach for PS with ease, speed and accuracy.
"Only \$149 for 3 month Online Course"
"Free Resources-30 day online access & Diagnostic Test"
"Unlimited Access to over 120 free video lessons - try it yourself"

Math Revolution GMAT Instructor
Joined: 16 Aug 2015
Posts: 6815
GMAT 1: 760 Q51 V42
GPA: 3.82
Re: Math Revolution Approach (PS)  [#permalink]

Show Tags

14 Jul 2016, 00:08
What is the prime factors’ number of 24?
A. 2
B. 3
C. 4
D. 5
E. 6

ANS: From 24=3(2^3), we get 2,2,2 and 3. Hence, the number of prime factors is 4.
_________________

MathRevolution: Finish GMAT Quant Section with 10 minutes to spare
The one-and-only World’s First Variable Approach for DS and IVY Approach for PS with ease, speed and accuracy.
"Only \$149 for 3 month Online Course"
"Free Resources-30 day online access & Diagnostic Test"
"Unlimited Access to over 120 free video lessons - try it yourself"

Math Revolution GMAT Instructor
Joined: 16 Aug 2015
Posts: 6815
GMAT 1: 760 Q51 V42
GPA: 3.82
Re: Math Revolution Approach (PS)  [#permalink]

Show Tags

14 Jul 2016, 20:25
a is an integer greater than 19 but less than 31, b is an integer greater than 29 but less than 41, what is the range of a/b?
A. 1/4
B. 1/2
C. 3/4
D. 1
E. 5/4

ANS: From 20≤a≤30 and 30≤b≤40, we get 1/2=20/40≤a/b≤30/30=1. Hence, range=Max-min=1-1/2=1/2 and the correct answer is B.
_________________

MathRevolution: Finish GMAT Quant Section with 10 minutes to spare
The one-and-only World’s First Variable Approach for DS and IVY Approach for PS with ease, speed and accuracy.
"Only \$149 for 3 month Online Course"
"Free Resources-30 day online access & Diagnostic Test"
"Unlimited Access to over 120 free video lessons - try it yourself"

Math Revolution GMAT Instructor
Joined: 16 Aug 2015
Posts: 6815
GMAT 1: 760 Q51 V42
GPA: 3.82
Re: Math Revolution Approach (PS)  [#permalink]

Show Tags

18 Jul 2016, 03:15
What number is 72 more than three-fourth of itself?
A. 138
B. 225
C. 288
D. 324
E. 336

ANS: From n=72+(3n/4), n/4=72, n=72(4)=288
Hence, the correct answer is C
_________________

MathRevolution: Finish GMAT Quant Section with 10 minutes to spare
The one-and-only World’s First Variable Approach for DS and IVY Approach for PS with ease, speed and accuracy.
"Only \$149 for 3 month Online Course"
"Free Resources-30 day online access & Diagnostic Test"
"Unlimited Access to over 120 free video lessons - try it yourself"

Math Revolution GMAT Instructor
Joined: 16 Aug 2015
Posts: 6815
GMAT 1: 760 Q51 V42
GPA: 3.82
Re: Math Revolution Approach (PS)  [#permalink]

Show Tags

18 Jul 2016, 08:24
If a, b are integers and |a-b|=8, which of the following is the smallest possible value of ab?
A. -16
B. 0
C. 16
D. 7
E. 40

ANS: a=4, b=-4. Hence, the answer is A.
_________________

MathRevolution: Finish GMAT Quant Section with 10 minutes to spare
The one-and-only World’s First Variable Approach for DS and IVY Approach for PS with ease, speed and accuracy.
"Only \$149 for 3 month Online Course"
"Free Resources-30 day online access & Diagnostic Test"
"Unlimited Access to over 120 free video lessons - try it yourself"

Math Revolution GMAT Instructor
Joined: 16 Aug 2015
Posts: 6815
GMAT 1: 760 Q51 V42
GPA: 3.82
Re: Math Revolution Approach (PS)  [#permalink]

Show Tags

24 Jul 2016, 01:43
What is the units digit of 17^381?
A. 1
B. 3
C. 5
D. 7
E. 9

ANS: From ~7^1=~7, ~7^2=9, ~7^3=~3, ~7^4=~1, the units digit is 7-->9-->3-->1-->7, and it repeats like this. Then from 17^381=17^(4(95)+1), we can see that the units digit is same as 17^1, which is 7.
The answer is, then, D.
_________________

MathRevolution: Finish GMAT Quant Section with 10 minutes to spare
The one-and-only World’s First Variable Approach for DS and IVY Approach for PS with ease, speed and accuracy.
"Only \$149 for 3 month Online Course"
"Free Resources-30 day online access & Diagnostic Test"
"Unlimited Access to over 120 free video lessons - try it yourself"

Math Revolution GMAT Instructor
Joined: 16 Aug 2015
Posts: 6815
GMAT 1: 760 Q51 V42
GPA: 3.82
Re: Math Revolution Approach (PS)  [#permalink]

Show Tags

25 Jul 2016, 18:37
What is the scope including 1/11+1/12+1/13+......+1/20?
A 1/6~1/5
B. 1/5~1/4
C. 1/4~1/3
D. 1/3~1/2
E. 1/2~1

ANS: The sum of a sequence of reciprocals is determined by the first and the end term. So, since 1/2=10/20<1/11+1/12+1/13+......+1/20<10/11<10/10=1, the correct answer is E.
_________________

MathRevolution: Finish GMAT Quant Section with 10 minutes to spare
The one-and-only World’s First Variable Approach for DS and IVY Approach for PS with ease, speed and accuracy.
"Only \$149 for 3 month Online Course"
"Free Resources-30 day online access & Diagnostic Test"
"Unlimited Access to over 120 free video lessons - try it yourself"

Math Revolution GMAT Instructor
Joined: 16 Aug 2015
Posts: 6815
GMAT 1: 760 Q51 V42
GPA: 3.82
Re: Math Revolution Approach (PS)  [#permalink]

Show Tags

26 Jul 2016, 17:27
If two integers x,y (x>y) are selected from -5 to 4(inclusive), how many cases are there?
A. 15
B. 18
C. 36
D. 45
E. 90

ANS: 10C2=45. Hence, the correct answer is D.
_________________

MathRevolution: Finish GMAT Quant Section with 10 minutes to spare
The one-and-only World’s First Variable Approach for DS and IVY Approach for PS with ease, speed and accuracy.
"Only \$149 for 3 month Online Course"
"Free Resources-30 day online access & Diagnostic Test"
"Unlimited Access to over 120 free video lessons - try it yourself"

Math Revolution GMAT Instructor
Joined: 16 Aug 2015
Posts: 6815
GMAT 1: 760 Q51 V42
GPA: 3.82
Math Revolution Approach (PS)  [#permalink]

Show Tags

31 Jul 2016, 08:02
Which of the following is equal to 1(1/5)%?
A. 0.012/100
B. 0.12/100
C. 1.2/100
D. 12/100
E. 12/10

ANS: If we substitute %=1/100, we get 1(1/5)%=(1+1/5)%=(6/5)%=( 6/5)( 1/100)= (1.2)/100

So, the answer is C.
_________________

MathRevolution: Finish GMAT Quant Section with 10 minutes to spare
The one-and-only World’s First Variable Approach for DS and IVY Approach for PS with ease, speed and accuracy.
"Only \$149 for 3 month Online Course"
"Free Resources-30 day online access & Diagnostic Test"
"Unlimited Access to over 120 free video lessons - try it yourself"

Math Revolution GMAT Instructor
Joined: 16 Aug 2015
Posts: 6815
GMAT 1: 760 Q51 V42
GPA: 3.82
Re: Math Revolution Approach (PS)  [#permalink]

Show Tags

04 Aug 2016, 03:45
1+2+2^2+2^3+2^4+2^5=？
A. (2^3-1)(2^3+1)
B. 2^6+1
C. 2^5-1
D. 2^5+1
E. 2^5-2

ANS: From 1+2+2^2+2^3+2^4+2^5=1(2^6-1)/(2-1)=2^6-1=(2^3-1)(2^3+1), the correct answer is A.
_________________

MathRevolution: Finish GMAT Quant Section with 10 minutes to spare
The one-and-only World’s First Variable Approach for DS and IVY Approach for PS with ease, speed and accuracy.
"Only \$149 for 3 month Online Course"
"Free Resources-30 day online access & Diagnostic Test"
"Unlimited Access to over 120 free video lessons - try it yourself"

Math Revolution GMAT Instructor
Joined: 16 Aug 2015
Posts: 6815
GMAT 1: 760 Q51 V42
GPA: 3.82
Re: Math Revolution Approach (PS)  [#permalink]

Show Tags

04 Aug 2016, 18:20
If (x^3-2x^2+x-1)^2-1=(x-a)(x-b)(x-c)(x-d)(x-e)(x-f), then abcdef=?
A. 0
B. 25
C. -25
D. 24
E. -24

ANS: If we substitute x=0, from (-1)^2-1=(-a)(-b)(-c)(-d)(-e)(-f)=abcdef, we get abcdef=0.
_________________

MathRevolution: Finish GMAT Quant Section with 10 minutes to spare
The one-and-only World’s First Variable Approach for DS and IVY Approach for PS with ease, speed and accuracy.
"Only \$149 for 3 month Online Course"
"Free Resources-30 day online access & Diagnostic Test"
"Unlimited Access to over 120 free video lessons - try it yourself"

Math Revolution GMAT Instructor
Joined: 16 Aug 2015
Posts: 6815
GMAT 1: 760 Q51 V42
GPA: 3.82
Re: Math Revolution Approach (PS)  [#permalink]

Show Tags

07 Aug 2016, 16:53
Which of the following lines has x-intercept and y-intercept that are integers?
A. y=3x+1
B. y=√x+1
C. y=-2/x
D. y=x^2-1
E. xy=1

ANS: Values that satisfy y=x^2-1 are (x,y)=(-1,0),(1,0),(0,-1). Hence, they are all integers and the correct answer is D.
_________________

MathRevolution: Finish GMAT Quant Section with 10 minutes to spare
The one-and-only World’s First Variable Approach for DS and IVY Approach for PS with ease, speed and accuracy.
"Only \$149 for 3 month Online Course"
"Free Resources-30 day online access & Diagnostic Test"
"Unlimited Access to over 120 free video lessons - try it yourself"

Math Revolution GMAT Instructor
Joined: 16 Aug 2015
Posts: 6815
GMAT 1: 760 Q51 V42
GPA: 3.82
Re: Math Revolution Approach (PS)  [#permalink]

Show Tags

08 Aug 2016, 17:24
What is the tens digit of 7^381?
A. 0
B. 3
C. 5
D. 7
E. 9

ANS: From ~7^1=~07, ~7^2=~49, ~7^3=~43, ~7^4=~01, the tens digit repeats 0-->4-->4-->0-->0. Then, from 7^381=7^(4(95)+1), the tens digit is same as ~7^1. Hence, it is 0.
_________________

MathRevolution: Finish GMAT Quant Section with 10 minutes to spare
The one-and-only World’s First Variable Approach for DS and IVY Approach for PS with ease, speed and accuracy.
"Only \$149 for 3 month Online Course"
"Free Resources-30 day online access & Diagnostic Test"
"Unlimited Access to over 120 free video lessons - try it yourself"

Math Revolution GMAT Instructor
Joined: 16 Aug 2015
Posts: 6815
GMAT 1: 760 Q51 V42
GPA: 3.82
Re: Math Revolution Approach (PS)  [#permalink]

Show Tags

22 Aug 2016, 18:52
If 1/(x(x+1))+1/((x+1)(x+2))=1/(x+1), what is the value of x?
A. √2
B. ±√2
C. 1
D. 2
E. √5

*Answer: If we solve the question, we get x=±√2.
_________________

MathRevolution: Finish GMAT Quant Section with 10 minutes to spare
The one-and-only World’s First Variable Approach for DS and IVY Approach for PS with ease, speed and accuracy.
"Only \$149 for 3 month Online Course"
"Free Resources-30 day online access & Diagnostic Test"
"Unlimited Access to over 120 free video lessons - try it yourself"

Re: Math Revolution Approach (PS) &nbs [#permalink] 22 Aug 2016, 18:52

Go to page   Previous    1   2   3   4   5   6   7   8   9   10   11  ...  29    Next  [ 568 posts ]

Display posts from previous: Sort by

Math Revolution Approach (PS)

 new topic post reply Question banks Downloads My Bookmarks Reviews Important topics

Moderator: souvonik2k

 Powered by phpBB © phpBB Group | Emoji artwork provided by EmojiOne Kindly note that the GMAT® test is a registered trademark of the Graduate Management Admission Council®, and this site has neither been reviewed nor endorsed by GMAC®.