NEW HERE? LEARN MORE
closeclose
It is currently 19 Apr 2024, 01:00
Register
GMAT Focus Tests
Decision Tracker
My Rewards
New posts
New comers' posts

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.
Go to My Error Log Learn more
Close
Request Expert Reply
Confirm Cancel

Given that p and q are positive, prime numbers greater than

10 posts Go to First Unread Post
Print view
NEW TOPIC
POST REPLY
Question banks

GMAT Question Banks

Downloads
My Bookmarks
Reviews
SORT BY:
Date
Kudos
User avatar
actleader
Manager
Manager
Joined: 25 Jun 2012
Posts: 54
Given that p and q are positive, prime numbers greater than [#permalink] New post  10 Nov 2012, 05:17
14
Bookmarks
00:00
A
B
C
D
E

Difficulty:

55% (hard)

Question Stats:

60% (01:48) correct 40% (01:50) wrong based on 187 sessions
Hide Show timer Statistics
Given that p and q are positive, prime numbers greater than 3, what is the product of 2p and 4q?

(1) The Least Common Multiple (LCM) of 2p and 4q is 140

(2) The Greatest Common Divisor (GCD) of 2p and 4q is 2.
ShowHide Answer
Official Answer
Official Answer and Stats are available only to registered users. Register/Login.
request expert reply
User avatar
L
Bunuel
Math Expert
Joined: 02 Sep 2009
Posts: 92749
CAT Tests Forum Quiz Mode
Re: Given that p and q are positive, prime numbers greater than [#permalink] New post  10 Nov 2012, 05:24
4
Bookmarks
Expert Reply
Given that p and q are positive, prime numbers greater than 3, what is the product of 2p and 4q?

(1) The Least Common Multiple (LCM) of 2p and 4q is 140 --> 140=2^2*5*7. Since we know that p and q are prime numbers greater than 3 and factors of 140, then p=5 and q=7 or vise-versa (p=q=5 or p=q=7 is not possible because in this case LCM won't be 140, it would be less). Sufficient.

(2) The Greatest Common Divisor (GCD) of 2p and 4q is 2. This statement just implies that \(p\neq{q}\), thus any two different primes greater than 3 will satisfy this condition. Not sufficient.

Answer: A.

Hope it's clear.
_________________
New to the GMAT CLUB Forum?

My Signature Questions' Collection:


What are GMAT Club Tests?
Extra-hard Quant Tests with Brilliant Analytics
Signature Read More
User avatar
P
mvictor
Board of Directors
Joined: 17 Jul 2014
Posts: 2164
Location: United States (IL)
Concentration: Finance, Economics
Schools: Stanford '20 (WD)
GMAT 1: 650 Q49 V30
GPA: 3.92
WE:General Management (Transportation)
GMAT ToolKit User Reviews Badge
Re: Given that p and q are positive, prime numbers greater than [#permalink] New post  01 Jun 2017, 15:46
I got to A the same way Bunuel explained.
we have 2p & 4q
since p and q are primes and definitely not even, pq will be 35 (140 / 2 = 70, and we have one more factor of 2 = 35)
since the question indirectly asks for pq - we can answer the question.

I can see why some guys would pick C - the product of two numbers is the product of LCM and GCF of these two numbers.
unfortunately, it is not the case, and B itself is not sufficient either.
avatar
B
mcm2112
Intern
Intern
Joined: 18 Aug 2015
Posts: 16
Location: United States
GPA: 3.38
Re: Given that p and q are positive, prime numbers greater than [#permalink] New post  01 Jun 2017, 16:19
Ok. I am really confused on this. If the first statement is not true, how can it be sufficient to answer the question. If the LCM is <140, then that proves this statement is false. Would any answer you arrive at using a false statement be false?
User avatar
P
mvictor
Board of Directors
Joined: 17 Jul 2014
Posts: 2164
Location: United States (IL)
Concentration: Finance, Economics
Schools: Stanford '20 (WD)
GMAT 1: 650 Q49 V30
GPA: 3.92
WE:General Management (Transportation)
GMAT ToolKit User Reviews Badge
Re: Given that p and q are positive, prime numbers greater than [#permalink] New post  01 Jun 2017, 17:44
mcm2112 wrote:
Ok. I am really confused on this. If the first statement is not true, how can it be sufficient to answer the question. If the LCM is <140, then that proves this statement is false. Would any answer you arrive at using a false statement be false?


Statements are always true
First statement says lcm is 140
Not that it is less than 140

Posted from my mobile device
User avatar
P
amanvermagmat
Retired Moderator
Joined: 22 Aug 2013
Posts: 1187
Location: India
Re: Given that p and q are positive, prime numbers greater than [#permalink] New post  01 Jun 2017, 23:51
mcm2112 wrote:
Ok. I am really confused on this. If the first statement is not true, how can it be sufficient to answer the question. If the LCM is <140, then that proves this statement is false. Would any answer you arrive at using a false statement be false?


Hi

When we consider a statement in DS questions, we have to take that statement to be completely true, and then try to arrive at an answer to the given question using the data of this statement.

So in case of first statement, we have to assume that LCM of 2p and 4q is 140 only, and then evaluate whether the required answer (product of 2p and 4q) can be found using this data.
If we can get a unique value for the required product, then we have found our answer and we conclude that the statement is sufficient,
But if we do not have a unique value, then the answer has not been found and we conclude that the statement is not sufficient.
avatar
B
mcm2112
Intern
Intern
Joined: 18 Aug 2015
Posts: 16
Location: United States
GPA: 3.38
Re: Given that p and q are positive, prime numbers greater than [#permalink] New post  02 Jun 2017, 13:48
Apologies. I got it after correctly reading how mvictor explained the question.
avatar
B
akulsoni100
Intern
Intern
Joined: 28 Mar 2017
Posts: 1
Location: India
Concentration: General Management, Strategy
Schools: Rotman '20
GMAT 1: 620 Q45 V36
GPA: 3.61
Re: Given that p and q are positive, prime numbers greater than [#permalink] New post  13 Jun 2017, 15:58
can someone clarify the statement 2.
thanks
User avatar
L
Bunuel
Math Expert
Joined: 02 Sep 2009
Posts: 92749
CAT Tests Forum Quiz Mode
Re: Given that p and q are positive, prime numbers greater than [#permalink] New post  14 Jun 2017, 05:50
Expert Reply
akulsoni100 wrote:
can someone clarify the statement 2.
thanks


We know that p and q are primes greater than 3, so they are some odd primes.

(2) says: the Greatest Common Divisor (GCD) of 2p and 4q is 2. Now, since both p and q are primes greater than 3, then this will be true for any distinct p and q, for example, the GCD of 2*5 and 2*7 is 2. This is because primes do not share any common factor but 1.

The only case this won't be true is when p = q. For example, if p = q = 5, then GCD of 2*5 and 2*5 will be 10, not 2. So, this statement just implies that p≠q, thus any two different primes greater than 3 will satisfy this condition. Not sufficient.

Hope it's clear.
_________________
New to the GMAT CLUB Forum?

My Signature Questions' Collection:


What are GMAT Club Tests?
Extra-hard Quant Tests with Brilliant Analytics
Signature Read More
User avatar
bumpbot
Non-Human User
Joined: 09 Sep 2013
Posts: 32536
Re: Given that p and q are positive, prime numbers greater than [#permalink] New post  04 Jan 2024, 14:13
Hello from the GMAT Club BumpBot!

Thanks to another GMAT Club member, I have just discovered this valuable topic, yet it had no discussion for over a year. I am now bumping it up - doing my job. I think you may find it valuable (esp those replies with Kudos).

Want to see all other topics I dig out? Follow me (click follow button on profile). You will receive a summary of all topics I bump in your profile area as well as via email.
_________________
GMAT Books | GMAT Club Tests | Best Prices on GMAT Courses | GMAT Mobile App | Math Resources | Verbal Resources
Signature Read More
GMAT Club Bot
gmatclubot
Re: Given that p and q are positive, prime numbers greater than [#permalink]
04 Jan 2024, 14:13
NEW TOPIC
POST REPLY
Downloads
My Bookmarks
Reviews
Moderator:
Bunuel
Math Expert
92749 posts

cron

Powered by phpBB © phpBB Group | Emoji artwork provided by EmojiOne
Main navigation
GMAT Resources
Partners
MBA Resources
www.gmac.com|www.mba.com | | GMAT Club Rules | Terms and Conditions