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

 It is currently 18 Sep 2018, 22:42

### 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

# If r is a positive integer, does r have exactly four distinct positive

Author Message
TAGS:

### Hide Tags

Moderator
Joined: 22 Jun 2014
Posts: 1048
Location: India
Concentration: General Management, Technology
GMAT 1: 540 Q45 V20
GPA: 2.49
WE: Information Technology (Computer Software)
If r is a positive integer, does r have exactly four distinct positive  [#permalink]

### Show Tags

26 Sep 2017, 10:53
1
00:00

Difficulty:

25% (medium)

Question Stats:

74% (00:37) correct 26% (00:37) wrong based on 53 sessions

### HideShow timer Statistics

If r is a positive integer, does r have exactly four distinct positive factors?

(1) r is the product of two different prime numbers

(2) r = 6

_________________

---------------------------------------------------------------
Target - 720-740
http://gmatclub.com/forum/information-on-new-gmat-esr-report-beta-221111.html
http://gmatclub.com/forum/list-of-one-year-full-time-mba-programs-222103.html

PS Forum Moderator
Joined: 25 Feb 2013
Posts: 1213
Location: India
GPA: 3.82
Re: If r is a positive integer, does r have exactly four distinct positive  [#permalink]

### Show Tags

26 Sep 2017, 11:11
HKD1710 wrote:
If r is a positive integer, does r have exactly four distinct positive factors?

(1) r is the product of two different prime numbers

(2) r = 6

Statement 1: $$r=p_{1}*p_{2}$$, where $$p_{1}$$ & $$p_{2}$$ are two different prime nos.

therefore no of factors $$= (1+1)*(1+1) = 4$$. Sufficient

Statement 2: directly provides the value of r, hence we can definitely calculate number of factors (either Yes or NO). Hence Sufficient

Although not required but just FYI $$r=6=2*3$$. Hence no of factors $$= (1+1)*(1+1) =4$$

Option D
Intern
Joined: 04 Nov 2015
Posts: 33
Re: If r is a positive integer, does r have exactly four distinct positive  [#permalink]

### Show Tags

27 Sep 2017, 00:45
niks18 wrote:
HKD1710 wrote:
If r is a positive integer, does r have exactly four distinct positive factors?

(1) r is the product of two different prime numbers

(2) r = 6

Statement 1: $$r=p_{1}*p_{2}$$, where $$p_{1}$$ & $$p_{2}$$ are two different prime nos.

therefore no of factors $$= (1+1)*(1+1) = 4$$. Sufficient

Statement 2: directly provides the value of r, hence we can definitely calculate number of factors (either Yes or NO). Hence Sufficient

Although not required but just FYI $$r=6=2*3$$. Hence no of factors $$= (1+1)*(1+1) =4$$

Option D

Hi ,

I suppose the answer should be B.
In option A it is given that it is the product of 2 different prime numbers but that prime numbers can itself have some powers .example 2^3 . 3^5 then in this case the number of factors are (3+1)(5+1) that is a total of 24.Hence this option is not sufficient.

Experts please clarify if my understanding is correct.

Regards,
Sandeep
PS Forum Moderator
Joined: 25 Feb 2013
Posts: 1213
Location: India
GPA: 3.82
Re: If r is a positive integer, does r have exactly four distinct positive  [#permalink]

### Show Tags

27 Sep 2017, 01:07
sandeep211986 wrote:
niks18 wrote:
HKD1710 wrote:
If r is a positive integer, does r have exactly four distinct positive factors?

(1) r is the product of two different prime numbers

(2) r = 6

Statement 1: $$r=p_{1}*p_{2}$$, where $$p_{1}$$ & $$p_{2}$$ are two different prime nos.

therefore no of factors $$= (1+1)*(1+1) = 4$$. Sufficient

Statement 2: directly provides the value of r, hence we can definitely calculate number of factors (either Yes or NO). Hence Sufficient

Although not required but just FYI $$r=6=2*3$$. Hence no of factors $$= (1+1)*(1+1) =4$$

Option D

Hi ,

I suppose the answer should be B.
In option A it is given that it is the product of 2 different prime numbers but that prime numbers can itself have some powers .example 2^3 . 3^5 then in this case the number of factors are (3+1)(5+1) that is a total of 24.Hence this option is not sufficient.

Experts please clarify if my understanding is correct.

Regards,
Sandeep

Hi sandeep211986

My interpretation of statement 1 is that r is simply a product of two prime nos. if prime nos are raised to any power, then it will not be a prime number but it will simply be a composite number/integer. But as per the language of statement 1 it mentions only prime numbers. for example the illustration you have chosen r becomes 1944 and 1944 is not a product of only two prime nos but can be represented as a product of multiple numbers.

I guess the owner of the topic HKD1710 can throw some light on the language of statement 1
CR & LSAT Forum Moderator
Status: He came. He saw. He conquered. -- Studying for the LSAT -- Corruptus in Extremis
Joined: 31 Jul 2017
Posts: 365
Location: United States
Concentration: Finance, Economics
Re: If r is a positive integer, does r have exactly four distinct positive  [#permalink]

### Show Tags

27 Sep 2017, 12:10
sandeep211986 wrote:
niks18 wrote:
HKD1710 wrote:
If r is a positive integer, does r have exactly four distinct positive factors?

(1) r is the product of two different prime numbers

(2) r = 6

Statement 1: $$r=p_{1}*p_{2}$$, where $$p_{1}$$ & $$p_{2}$$ are two different prime nos.

therefore no of factors $$= (1+1)*(1+1) = 4$$. Sufficient

Statement 2: directly provides the value of r, hence we can definitely calculate number of factors (either Yes or NO). Hence Sufficient

Although not required but just FYI $$r=6=2*3$$. Hence no of factors $$= (1+1)*(1+1) =4$$

Option D

Hi ,

I suppose the answer should be B.
In option A it is given that it is the product of 2 different prime numbers but that prime numbers can itself have some powers .example 2^3 . 3^5 then in this case the number of factors are (3+1)(5+1) that is a total of 24.Hence this option is not sufficient.

Experts please clarify if my understanding is correct.

Regards,
Sandeep

hi Sandeep,

2^3 = 8, which is not a prime number. The question states that R is the product of two prime numbers. If we have two prime numbers put to the Nth power, we are changing the question. I think you may have over thought this.

I hope this helps!

My opinion is D
_________________

D-Day: November 18th, 2017

Need a laugh and a break? Go here: https://gmatclub.com/forum/mental-break-funny-videos-270269.html

Re: If r is a positive integer, does r have exactly four distinct positive &nbs [#permalink] 27 Sep 2017, 12:10
Display posts from previous: Sort by

# Events & Promotions

 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®.