Question involving absolute values

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Question involving absolute values

by Auzbee » Mon Dec 31, 2007 12:18 pm
If a and b are integers, and |a| > |b|, is a · |b| < a – b?

1. a less than zero
2. ab greater than equal to zero

Would love to see explanation for this one. Can this be cracked in 2 min time?
Last edited by Auzbee on Mon Dec 31, 2007 2:24 pm, edited 1 time in total.

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by beingAndNothing » Mon Dec 31, 2007 2:20 pm
Auzbee:

I am not sure as to what exactly is the inequality, since formatting is messing up what you've written. Anyways, I would rewrite the inequality by dividing both sides by |b|.
Now a/|b| would be greater than 1 or less than -1 depending on a > 0 or a < 0. Similarly b/|b| = 1 or -1 depending upon the sign.

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by Auzbee » Mon Dec 31, 2007 2:25 pm
I am not sure as to what exactly is the inequality, since formatting is messing up what you've written.
I have corrected the question in my edit. Let me know your reply.

Thanks

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by StarDust845 » Tue Jan 01, 2008 9:38 pm
Is the answer E?

I just put in different values for a and b and arrived at that answer. I wish there were some elegant solution to this problem.

Calista.

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by Auzbee » Tue Jan 01, 2008 9:48 pm
Can't seem to find the OA, but it is from one of the MGMAT CATs. The OA should be between C or E.

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by sirikesav » Wed Jan 02, 2008 6:26 am
I will go with answer C.Please let me know whether it is correct or not