ps 500 test21 # 14

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ps 500 test21 # 14

by dunkin77 » Sun Apr 08, 2007 12:20 pm
Hi,

I thought the answer was C) but actually correct one is D) - can anyone explain why?


14. If y + | y | = 0, which of the following must be true?
(A) y > 0
(B) y≥0
(C) y < 0
(D) y&#8804;0
(E) y = 0

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by 800GMAT » Sun Apr 08, 2007 6:03 pm
|y| is always positive. To satisfy the inequality, y must be negative.
Another value of y that satisfies the inequality is 0

Also by POE:

(A) y>0....y can be negative
(B) y>=0....y can be negative
(C) y<0....y can be zero
(E) y=0.....y can be negative


Hence A,B,C,E need not be true or must not be true

Therefore D

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by dunkin77 » Sun Apr 08, 2007 11:38 pm
Okay:)

To satisfy the condition, we need a condition that meet both Y are negative AND zero.

Thanks!

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by 800GMAT » Mon Apr 09, 2007 8:12 pm
you got it!

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by Cybermusings » Mon Apr 09, 2007 11:28 pm
when y + | y | = 0, there are only two possiblities
When y itself = 0 ; then the actual and absolute value of y both would be zero and hence their sum would be zero#
Second possibility is that y is a negative number; in such a case the absolute value will become positive and hence the sum would be a resultant zero; Hence the possibility is that y is less than or equal to zero.
Hence D