If a, b and c are three integers, are they consecutive?

Question

(1) b = 2c
(2) a = b - 1

Taikiqi · Answer

DS Masters,

I wonder why the OA is A. Question is asking a,b,c are consecutive or not. S1 only provides information on b and c, how do we know anything about a? 
with S1 and S2, we know for sure the set is not consecutive. Therefore I believe the answer is C.

Please help.

Thanks.

Posted from my mobile device

Hoozan · Answer

Sorry for the confusion. The OA is "E" and not "A". You might want to give this question another try before selecting C

Taikiqi · Answer

Hi Hoozan,

Thanks, the answer is E. with the -3, -2 ,-1 be one of the outcomes from S1 and S2.

Posted from my mobile device

Hoozan · Answer

We can simplify the question and say that is b-1, b, b/2 consecutive?

Clearly each statement by itself is not sufficient to answer the given question.

Combining we could have 
a = 3
b = 4
c = 2

In that case we get Yes,  a,b,  and  c  are consecutive.

On the other hand if 
a = 7
b = 8
c = 4

In that case we get No,  a, b,  and  c  are not consecutive

Answer: (E)

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If a, b and c are three integers, are they consecutive?

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If a, b and c are three integers, are they consecutive?

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