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

It is currently 15 Aug 2018, 21:18

Close

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
Your Progress

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

Not interested in getting valuable practice questions and articles delivered to your email? No problem, unsubscribe here.

Close

Request Expert Reply

Confirm Cancel

Fresh Meat!!!

  new topic post reply Question banks Downloads My Bookmarks Reviews Important topics  
Author Message
TAGS:

Hide Tags

Senior Manager
Senior Manager
avatar
Joined: 16 Dec 2011
Posts: 368
Re: Fresh Meat!!!  [#permalink]

Show Tags

New post 19 Apr 2013, 10:19
1
4. The functions f and g are defined for all the positive integers n by the following rule: f(n) is the number of perfect squares less than n and g(n) is the number of primes numbers less than n. If f(x) + g(x) = 16, then x is in the range:

A. 30 < x < 36
B. 30 < x < 37
C. 31 < x < 37
D. 31 < x < 38
E. 32 < x < 38

For x = 37, f(x) + g(x) = 5 + 12 = 17
For x = 36, f(x) + g(x) = 5 + 11 = 16
For x = 32, f(x) + g(x) = 5 + 11 = 16
For x = 31, f(x) + g(x) = 5 + 10 = 15
So, 31 < x < 37

Correct answer is C
Senior Manager
Senior Manager
avatar
Joined: 16 Dec 2011
Posts: 368
Re: Fresh Meat!!!  [#permalink]

Show Tags

New post 19 Apr 2013, 10:19
1
5. Which of the following is a factor of 18!+1?

A. 15
B. 17
C. 19
D. 33
E. 39

18! and 18!+1 are consecutive integers and so they do not have any common factor except 1.
15, 17, 33 (=3*11), and 39 (=3*13) are factors of 18! and none of those can be a factor of 18!+1.
So, only 19 can be a factor of 18!+1

Correct answer is C.
Senior Manager
Senior Manager
avatar
Joined: 16 Dec 2011
Posts: 368
Re: Fresh Meat!!!  [#permalink]

Show Tags

New post 19 Apr 2013, 10:20
2
6. If the least common multiple of a positive integer x, 4^3 and 6^5 is 6^6. Then x can take how many values?

A. 1
B. 6
C. 7
D. 30
E. 36

Numbers are: x, 2^6, and (2^5)*(3^5)
LCM of the numbers = (2^6)*(3^6)
As 3^6 is not part of second and third numbers, it must be part of x.
So, lowest and highest values of x can be 3^6 and 6^6 {=(3^6)*(2^6)}.
So the values that x can take are: (3^6)*(2^0), (3^6)*(2^1), (3^6)*(2^2), (3^6)*(2^3), (3^6)*(2^4), (3^6)*(2^5), and (3^6)*(2^6).

Correct answer is C.
Senior Manager
Senior Manager
avatar
Joined: 16 Dec 2011
Posts: 368
Re: Fresh Meat!!!  [#permalink]

Show Tags

New post 19 Apr 2013, 10:20
1
7. The greatest common divisor of two positive integers is 25. If the sum of the integers is 350, then how many such pairs are possible?

A. 1
B. 2
C. 3
D. 4
E. 5

350 = 25 * 14
To have the GCD of two numbers to be 25, we need to split 14 into two co-prime numbers. Such pairs of numbers are: (1,13), (3,11), and (5,9).

Correct answer is C.
Senior Manager
Senior Manager
avatar
Joined: 16 Dec 2011
Posts: 368
Re: Fresh Meat!!!  [#permalink]

Show Tags

New post 19 Apr 2013, 10:20
1
8. The product of a positive integer x and 377,910 is divisible by 3,300, then the least value of x is:

A. 10
B. 11
C. 55
D. 110
E. 330

377,910 = 3 * 3 * 10 * 4199
3,310 = 3 * 10 *10 * 11
So, x must have 10 and 11 as factors.
--> Least value of x is 110.

Correct answer is D.
Senior Manager
Senior Manager
avatar
Joined: 16 Dec 2011
Posts: 368
Re: Fresh Meat!!!  [#permalink]

Show Tags

New post 19 Apr 2013, 10:21
2
9. What is the 101st digit after the decimal point in the decimal representation of 1/3 + 1/9 + 1/27 + 1/37?

A. 0
B. 1
C. 5
D. 7
E. 8

1/3 = 0.333333……… (recurring 3)
1/9 = 0.111111……… (recurring 1)
1/27 = 0.037037…………. (recurring 037)
1/37 = 0.027027………….. (recurring 027)

1/3 + 1/9 + 1/27 + 1/37 =0.508508…………….. (recurring 508)
--> 8 will be in every 3rd position
--> 8 will be in 99th position
--> 0 will be in 101st position

Correct answer is A.
Senior Manager
Senior Manager
avatar
Joined: 16 Dec 2011
Posts: 368
Re: Fresh Meat!!!  [#permalink]

Show Tags

New post 19 Apr 2013, 10:21
1
10. If x is not equal to 0 and x^y=1, then which of the following must be true?

I. x=1
II. x=1 and y=0
III. x=1 or y=0

A. I only
B. II only
C. III only
D. I and III only
E. None

x^y=1 can be obtained by any of the following:
(a) y = 0 and x = any real number
(b) x = 1 and y = any real number
(c) x = -1 and y = any even number

I. For x=2 and y=0, x^y=1. So, this condition is not necessarily true.
II. For x=2 and y=0, x^y=1. For x=1 and y=5, x^y=1. So, this condition is not necessarily true.
III. For x=-1 and y=2, x^y=1. So, this condition is not necessarily true.

Correct answer is E.
Manager
Manager
avatar
Status: Looking to improve
Joined: 15 Jan 2013
Posts: 164
GMAT 1: 530 Q43 V20
GMAT 2: 560 Q42 V25
GMAT 3: 650 Q48 V31
Re: Fresh Meat!!!  [#permalink]

Show Tags

New post 19 Apr 2013, 13:54
1
Q4). The functions f and g are defined for all the positive integers n by the following rule: f(n) is the number of perfect squares less than n and g(n) is the number of primes numbers less than n. If f(x) + g(x) = 16, then x is in the range:

Answer - C


g(x) --> Primes - 2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37, 41
f(x) --> Squares - 1, 4, 9, 16, 25, 36

x = 32 ==> f(32) + g(32) = 5 + 11 = 16
_________________

KUDOS is a way to say Thank You

Manager
Manager
avatar
Status: Looking to improve
Joined: 15 Jan 2013
Posts: 164
GMAT 1: 530 Q43 V20
GMAT 2: 560 Q42 V25
GMAT 3: 650 Q48 V31
Re: Fresh Meat!!!  [#permalink]

Show Tags

New post 19 Apr 2013, 14:29
Q7) The greatest common divisor of two positive integers is 25. If the sum of the integers is 350, then how many such pairs are possible?

Answer is A

Since the GCM is 25, the 2 positive integers should have 5^2 as the only common factor. The 2 potential positive integers can be found by dividing 350 / 25 and finding unique prime factors that add up to the divisor.

350 / 25 = 14 and 14 = 11 + 3
_________________

KUDOS is a way to say Thank You

Manager
Manager
avatar
Status: Looking to improve
Joined: 15 Jan 2013
Posts: 164
GMAT 1: 530 Q43 V20
GMAT 2: 560 Q42 V25
GMAT 3: 650 Q48 V31
Re: Fresh Meat!!!  [#permalink]

Show Tags

New post 19 Apr 2013, 14:51
1
Q8) The product of a positive integer x and 377,910 is divisible by 3,300, then the least value of x is:

Answer is D

3,300 factors are 3 * 11 * 5 ^2 * 2^ 2
377,910 factors are 3^2 * 2 * 5 * 13 * 17 * 19

3,300 can be factor of x * 377,910 only if x has 5 * 11 * 2 as the minimum factors. Hence x is 110
_________________

KUDOS is a way to say Thank You

Manager
Manager
avatar
Status: Looking to improve
Joined: 15 Jan 2013
Posts: 164
GMAT 1: 530 Q43 V20
GMAT 2: 560 Q42 V25
GMAT 3: 650 Q48 V31
Re: Fresh Meat!!!  [#permalink]

Show Tags

New post 19 Apr 2013, 15:04
Q1) The length of the diagonal of square S, as well as the lengths of the diagonals of rhombus R are integers. The ratio of the lengths of the diagonals is 15:11:9, respectively. Which of the following could be the difference between the area of square S and the area of rhombus R?

I. 63
II. 126
III. 252


Answer is E

S diagonal : R diagonal 1 : R diagonal 2 = 15:11:9

Let's assume x is the unknown multiplier and the ratio of diagonals are 15x:11x:9x

\(Area of S =\frac{15x}{\sqrt{2}}\)

\(Area of R = 1/2 * 11x * 9x\)

\(Area of S - Area of R = \frac{225x - 99x}{2} = 63x\)

And I, II, II are multiples of 63 when x = 1, 2, 3
_________________

KUDOS is a way to say Thank You

Manager
Manager
avatar
Joined: 26 Feb 2013
Posts: 52
Concentration: Strategy, General Management
GMAT 1: 660 Q50 V30
WE: Consulting (Telecommunications)
Re: Fresh Meat!!!  [#permalink]

Show Tags

New post 20 Apr 2013, 00:06
1
1. The length of the diagonal of square S, as well as the lengths of the diagonals of rhombus R are integers. The ratio of the lengths of the diagonals is 15:11:9, respectively. Which of the following could be the difference between the area of square S and the area of rhombus R?

I. 63
II. 126
III. 252

A. I only
B. II only
C. III only
D. I and III only
E. I, II and III
My answer is D
Let the diagonals be 15x,11x and 9x.
Area of a Rhombus is .5*d1*d2
 .5*11x*9x=> 11*9*x2/2. = (99x^2)/2
 Area of square with diagonal 15x is (225x^2)/2
Difference in areas is 63x^2.
Difference can be 63, for X = 1 ; 126 for x=root2 and 252 for x=2.
However when x= root2, the diagonals are not integers. Hence only 2 values are possible. 63 and 252
Manager
Manager
avatar
Joined: 26 Feb 2013
Posts: 52
Concentration: Strategy, General Management
GMAT 1: 660 Q50 V30
WE: Consulting (Telecommunications)
Re: Fresh Meat!!!  [#permalink]

Show Tags

New post 20 Apr 2013, 00:06
1
3. How many different subsets of the set {0, 1, 2, 3, 4, 5} do not contain 0?

A. 16
B. 27
C. 31
D. 32
E. 64
My answer is D.
Total number of subsets that can be formed from {1,2,3,4,5} = 25 =32
Manager
Manager
avatar
Joined: 26 Feb 2013
Posts: 52
Concentration: Strategy, General Management
GMAT 1: 660 Q50 V30
WE: Consulting (Telecommunications)
Re: Fresh Meat!!!  [#permalink]

Show Tags

New post 20 Apr 2013, 00:06
1
4. The functions f and g are defined for all the positive integers n by the following rule: f(n) is the number of perfect squares less than n and g(n) is the number of primes numbers less than n. If f(x) + g(x) = 16, then x is in the range:

A. 30 < x < 36
B. 30 < x < 37
C. 31 < x < 37
D. 31 < x < 38
E. 32 < x < 38
My answer C
Squares less than 36 : 1,4,9,16,25 = 5 primes less than 36 : 2,3,5,7,11,13,17,19,23,29,31. =11 and sum =16.
Hence the max value N has to be less than 37 as N =38 will increase the number of primes by 1 and squares by 1. And the sum will be 18
Minimum values of N has to be 32, as any value less than 32 will decrease the number of primes by 1.and the sum will be 15
Manager
Manager
avatar
Joined: 26 Feb 2013
Posts: 52
Concentration: Strategy, General Management
GMAT 1: 660 Q50 V30
WE: Consulting (Telecommunications)
Re: Fresh Meat!!!  [#permalink]

Show Tags

New post 20 Apr 2013, 00:08
1
5. Which of the following is a factor of 18!+1?

A. 15
B. 17
C. 19
D. 33
E. 39
My answer is C.
15, 17,33 and 39 , perfectly divide into 18! Hence leave a reminder of 1, when they divide 18!+1. Hence can be eliminated , leaving 19 the answer.
Manager
Manager
avatar
Joined: 26 Feb 2013
Posts: 52
Concentration: Strategy, General Management
GMAT 1: 660 Q50 V30
WE: Consulting (Telecommunications)
Re: Fresh Meat!!!  [#permalink]

Show Tags

New post 20 Apr 2013, 00:08
1
6. If the least common multiple of a positive integer x, 4^3 and 6^5 is 6^6. Then x can take how many values?

A. 1
B. 6
C. 7
D. 30
E. 36
My Answer C
66 = 26 *36 and 65 = 25 *35 . 4^3 = 26
Hence X should have 36 and It can have 20 till 26 that is 7 values from 20*36 till 26*36
Manager
Manager
avatar
Joined: 26 Feb 2013
Posts: 52
Concentration: Strategy, General Management
GMAT 1: 660 Q50 V30
WE: Consulting (Telecommunications)
Re: Fresh Meat!!!  [#permalink]

Show Tags

New post 20 Apr 2013, 00:08
7. The greatest common divisor of two positive integers is 25. If the sum of the integers is 350, then how many such pairs are possible?

A. 1
B. 2
C. 3
D. 4
E. 5
My Answer C
Let the numbers be 25a and 25b. for these numbers to have 25 as the GCD, a and b must be co-prime i.e have only 1 as the common factor.
25a+25b=350 => a+b =14 , a and b are co prime. Hence the pairs of a and b are => (1,13) , (3,11) ,(5,9).
Manager
Manager
avatar
Joined: 26 Feb 2013
Posts: 52
Concentration: Strategy, General Management
GMAT 1: 660 Q50 V30
WE: Consulting (Telecommunications)
Re: Fresh Meat!!!  [#permalink]

Show Tags

New post 20 Apr 2013, 00:08
8. The product of a positive integer x and 377,910 is divisible by 3,300, then the least value of x is:

A. 10
B. 11
C. 55
D. 110
E. 330

My answer is D
(337910*x)/3300 , reduced will become (12667 *x)/110 and 12667 is not divisible by any of the factors of 110( 2 or 5 or any combinations of both). Hence X has to be 110. At least.
Manager
Manager
avatar
Joined: 26 Feb 2013
Posts: 52
Concentration: Strategy, General Management
GMAT 1: 660 Q50 V30
WE: Consulting (Telecommunications)
Re: Fresh Meat!!!  [#permalink]

Show Tags

New post 20 Apr 2013, 00:09
9. What is the 101st digit after the decimal point in the decimal representation of 1/3 + 1/9 + 1/27 + 1/37?

A. 0
B. 1
C. 5
D. 7
E. 8

My answer A
1/3 + 1/9 + 1/27 = 13/27. = .481481…
1/37=.027027…
13/27 + 1/27 = .508508..
Hence 101st digit is 0.(3*33 +2=> hence the second digit of the recurring decimal which is 0)
Manager
Manager
avatar
Joined: 26 Feb 2013
Posts: 52
Concentration: Strategy, General Management
GMAT 1: 660 Q50 V30
WE: Consulting (Telecommunications)
Re: Fresh Meat!!!  [#permalink]

Show Tags

New post 20 Apr 2013, 00:17
10. If x is not equal to 0 and x^y=1, then which of the following must be true?

I. x=1
II. x=1 and y=0
III. x=1 or y=0

A. I only
B. II only
C. III only
D. I and III only
E. None
My answer C.
Since the question is what MUST be true I would go with C. as X can be any integer apart form 0 and Y can be 0. It’s not a must for X=1 and y=0.
Re: Fresh Meat!!! &nbs [#permalink] 20 Apr 2013, 00:17

Go to page   Previous    1   2   3   4   5   6   7   8   9    Next  [ 168 posts ] 

Display posts from previous: Sort by

Fresh Meat!!!

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

Events & Promotions

PREV
NEXT


GMAT Club MBA Forum Home| About| Terms and Conditions and Privacy Policy| GMAT Club Rules| Contact| Sitemap

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®.