GCD

Expert replies

ketkoag: Legendary Member; Posts: 876; Joined: Thu Apr 10, 2008 8:14 am; Thanked: 13 times

by ketkoag » Sat May 30, 2009 4:24 am

m and n are integers, m*n=?
1) m/n=7/13
2) The greatest common divisor of m and n is 3

IMO: C please correct me if i am wrong.

Like this post

Source: Beat The GMAT — Data Sufficiency | Sat May 30, 2009 4:24 am

ssmiles08: Master | Next Rank: 500 Posts; Posts: 472; Joined: Sun Mar 29, 2009 6:54 pm; Thanked: 56 times

by ssmiles08 » Sat May 30, 2009 4:48 am

I got C too

Like this post

rahulg83: Legendary Member; Posts: 575; Joined: Tue Nov 04, 2008 2:58 amFollowed by: 4 members; Location: India; Thanked: 18 times; GMAT Score:710

by rahulg83 » Sat May 30, 2009 10:32 am

Yes C is the right choice.
Consider m = 13*k (k any integer)
n = 7*k (k any integer), note that 13 and 7 are prime.
Only way for the GCD to be equal to 3 is that m=13*3 and n=7*3
therefore m*n can be found using both statements but not by either 1st or 2nd

Like this post

Post new topic Post Reply

• Page 1 of 1

GMAT Course Reviews

560 reviews

1168 reviews

431 reviews

359 reviews

147 reviews

5/5

5 Star (560 Reviews)

"Target Test Prep is the closest to the official version of the GMAT exam, about 99% accuracy in terms of the quality and quantity of information. The course has excellently created singular sets of focused lessons and tests for every possible topic that one could come across in the official GMAT exam."

"The TTP course maximizes the efficiency of the time you spend studying. It will take time and effort but I could almost guarantee that if you complete the course exactly as it is laid out you will get an amazing score. They also have a very responsive team willing to help with any questions you might have."

"TTP has two things that I think no other test prep company offers: A teaching approach that reinforces understanding and an attitude that will give you the mental preparedness needed to succeed on the test. TTP gives you a deep understanding of the concept you need to know while teaching you how to think."

Write a Review