It is currently 18 Nov 2018, 14:26
My Tests

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.

For any positive integer n, π(n) represents the number of fa

  Question banks Downloads My Bookmarks Reviews Important topics  
Author Message
TAGS:
1 KUDOS received
Moderator
Moderator
User avatar
Joined: 18 Apr 2015
Posts: 4914
Followers: 74

Kudos [?]: 977 [1] , given: 4499

CAT Tests
For any positive integer n, π(n) represents the number of fa [#permalink] New post 04 Apr 2018, 12:33
1
This post received
KUDOS
Expert's post
00:00

Question Stats:

54% (00:53) correct 45% (01:00) wrong based on 22 sessions
For any positive integer n, \(\pi(n)\) represents the number of factors of n, inclusive of 1 and itself. a and b are prime numbers

Quantity A
Quantity B
\(\pi(a) + \pi(b)\)
\(\pi(a * b)\)


A. The quantity in Column A is greater
B. The quantity in Column B is greater
C. The two quantities are equal
D. The relationship cannot be determined from the information given
[Reveal] Spoiler: OA

_________________

Get the 2 FREE GREPrepclub Tests

1 KUDOS received
Manager
Manager
Joined: 22 Feb 2018
Posts: 90
Followers: 2

Kudos [?]: 65 [1] , given: 9

Re: For any positive integer n, π(n) represents the number of fa [#permalink] New post 04 Apr 2018, 15:43
1
This post received
KUDOS
Answer: C (DOUBTS)
A: P(a) + P(b)
The only factors of a prime number are 1 and the number itself.
So P(a) + P(b) always equals 2+2 = 4

B: P(a*b)
The factors of a*b are 1, a, b, a*b. Why not more than 4? Because no new divider is produced with multiplying a to b. If there were any it was a factor of a or b (a factor other than a and b themselves and a) and thus a or b couldn’t be prime. So factors of a*b are 4 numbers.
For example if a = 3 and b = 11 then P(a*b) = P(33) = 4 (1, 3, 11, 33)

A and B are both 4 and equal. The answer is C.
1 KUDOS received
Director
Director
User avatar
Joined: 07 Jan 2018
Posts: 539
Followers: 4

Kudos [?]: 465 [1] , given: 82

CAT Tests
Re: For any positive integer n, π(n) represents the number of fa [#permalink] New post 06 May 2018, 18:29
1
This post received
KUDOS
I have reservation on the ans
because it could be a case of \(a = b\)
and hence qty B can have 3 factors
_________________

This is my response to the question and may be incorrect. Feel free to rectify any mistakes

2 KUDOS received
GMAT Club Legend
GMAT Club Legend
User avatar
Joined: 07 Jun 2014
Posts: 4711
GRE 1: Q167 V156
WE: Business Development (Energy and Utilities)
Followers: 91

Kudos [?]: 1614 [2] , given: 376

CAT Tests
Re: For any positive integer n, π(n) represents the number of fa [#permalink] New post 06 May 2018, 18:39
2
This post received
KUDOS
Expert's post
amorphous wrote:
I have reservation on the ans
because it could be a case of \(a = b\)
and hence qty B can have 3 factors


I second that thought if a = b then \(\pi(a*b)\) will have 3 factors 1, a , b and a*b.
_________________

Sandy
If you found this post useful, please let me know by pressing the Kudos Button

Try our free Online GRE Test

Re: For any positive integer n, π(n) represents the number of fa   [#permalink] 06 May 2018, 18:39
Display posts from previous: Sort by

For any positive integer n, π(n) represents the number of fa

  Question banks Downloads My Bookmarks Reviews Important topics  


GRE Prep Club Forum Home| About| Terms and Conditions and Privacy Policy| GRE Prep Club Rules| Contact

Powered by phpBB © phpBB Group

Kindly note that the GRE® test is a registered trademark of the Educational Testing Service®, and this site has neither been reviewed nor endorsed by ETS®.