|
|
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
Track
Your Progress
Practice
Pays
Not interested in getting valuable practice questions and articles delivered to your email? No problem, unsubscribe here.
11 May 2021, 01:30
Kudos
Bookmarks
E
Be sure to select an answer first to save it in the Error Log before revealing the correct answer (OA)!
Difficulty:
35%
(medium)
Question Stats:
66% (01:02) correct
34%
(00:56)
wrong
based on 102
sessions
History
Date
Time
Result
Not Attempted Yet
What is the value of the greatest common divisor of integers a and b?
(1) a is divisible by 15.
(2) b = 2a
(1) a is divisible by 15.
(2) b = 2a
16 May 2021, 04:00
Kudos
Bookmarks
Bunuel
The easiest way would be just to try different numbers. Clearly (1) and (2) alone are not sufficient. Now if we take them together:
If \(a=15\) then \(b=2a=30\) and GCD of \(a\) and \(b\) is 15 but if \(a=30\) then \(b=2a=60\) and GCD of \(a\) and \(b\) is 30. Two different answers not sufficient.
Answer: E.
General Discussion
11 May 2021, 03:59
Kudos
Bookmarks
Bunuel
statement: 1 a is divisible by 15.
a=15k
i.e a can be 15, 30, 45, 60...etc
No information about b; hence, Not sufficient
Statement:2
b = 2a
or a is a factor of b or greatest common divisor of "a and b" will be equal to a
No information about a; Hence, Not sufficient
Combined
Value of a is not known; Hence, not sufficient
E is the answer IMO
