Manhattan GMAT Number Properties Question

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Manhattan GMAT Number Properties Question

by BSDesis » Fri Jan 08, 2010 12:55 pm
Greetings all. I'm beginning my studies for the GMAT, and am working through the Manhattan GMAT study guides.

One of the problem sets has a question that reads:

If 6 is not a factor of d, is 12d divisible by 6?

a) Yes
b) No
c) Cannot Be Determined

Manhattan records the answer as Yes, but I do not see why it is not CBD.
My reasoning: though 12 is divisible by 6, the problem does not state d to be an integer. Is there a term of art that I am missing that would imply this scenario?

Thanks.

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by Osirus@VeritasPrep » Fri Jan 08, 2010 12:57 pm
Which chapter is that?

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by BSDesis » Fri Jan 08, 2010 12:58 pm
osirus0830 wrote:Which chapter is that?
1

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by Osirus@VeritasPrep » Fri Jan 08, 2010 1:01 pm
For problems #1-11, use one or more prime boxes, if appropriate, to answer each question. YES, NO, or CANNOT BE DETERMINED. If your answer is CANNOT BE DETERMINED, use two numerical examples to show how the problem could go either way. All variables in problems #1 through #11 are assumed to be INTEGERS unless otherwise indicated.

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by mp2437 » Wed Jan 13, 2010 9:28 am
Since 12 is divisible by 6, it follows that 12d can be divisible by 6 for any number d.

Try plugging in values if you are still stuck. i.e - d = 7. 12*7 / 6 = 2 * 7 = 14.

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by Yes.WeCan » Wed Jan 13, 2010 1:19 pm
Like the OP posted.

Nowhere it says that d has to be an integer.

If d =1.1 12d = 13.2, cannot be divided by 6.

IF d = integer, then YES
IF d= not defined, then CBD