Question 244 Quant - OG 10th Ed

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Question 244 Quant - OG 10th Ed

by toshiblue » Tue Nov 25, 2008 8:10 am
Hello,

I'm just starting out my GMAT study journey and have come across a question for which I think I'm being very dense. I just don't understand the question, nor do I understand the answer. Maybe I'm trying to make more out of it than I should. However,

The question is:
If x is an integer and y = 3x + 2, which of the following CANNOT be a divisor of y?

A. 4
B. 5
C. 6
D. 7
E. 8

The answer is 6, because 3x can be divided by 3, but 3x+2 can't, therefore, 6 can't.

What am I missing - because to me, for the same reason that 3x+2 can't be divided by 6, it can't be divided by 5 either (for a small iteration from x=1 to 4, for instance).
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by gmataug08 » Tue Nov 25, 2008 8:40 am
when x= 1

y = 5 (eliminates choice B)

x= 2

y = 8 (eliminates A & E)

x= 4

y = 14 (eliminates D)

we cant get an integer value for X that would result Y as multiple of 6 , hence the ANSWER = C