If a and b are positive integers, is the ratio of a to b equal to 2:1?

Question

If a and b are positive integers, is the ratio of a to b equal to 2:1?
 
(1) a – b > 0 
(2) The ratio of a to c is 4 to 3 and the ratio of c to b is 3 to 2.

anamika4 · Answer

Option A states a>b. And it can be any number in other ratio as well
Option B is correct as A/b=2/1

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GMATinsight · Answer

Question  : is the ratio of a to b equal to 2:1?

Statement 1:  a – b > 0  
i.e. a > b
Case 1: a/b = 2:1 YES
Case 2: a/b = 3:1 NO
NOT SUFFICIENT

Statement 1]2:  The ratio of a to c is 4 to 3 and the ratio of c to b is 3 to 2 
a/c = 4/3 and c/b = 3/2

i.e. a:c:b = 4:3:2

i.e. a:b = 4:2 = 2:1
SUFFICIENT

Answer: option B

DavidTutorexamPAL · Answer

This is a Data Sufficiency question dealing with ratios and with no exact numbers.
Perfect for a Logical approach using the logic of ratios.

(1) We know that a > b are positive integers but know nothing else about a or b.
Therefore we cannot know anything about the ratio between them. (Is a twice b? Three times b?)
Insufficient.

(2) Now we're told that a:c = 4:3 and c:b = 3:2. Combining these two together gives a:c:b = 4:3:2.
This means that a:b = 4:2 = 2:1. Yes!

(B) is our answer.

If a and b are positive integers, is the ratio of a to b equal to 2:1?

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