yogeshagarwala wrote:
Please solve:
I believe its B but the MR says its D.
If \(|a|=b\) is \(a+b>ab\)?
First of all as \(|a|=b\) (\(b\) equals to absolute value of some number) then \(b\geq{0}\), as absolute value is always non-negative.
(1) \(a=-b\) (\(b=-a\)) --> so \(a\leq{0}\) and \(LHS=a+b=0\). But \(RHS=ab\leq{0}\) thus we can not say for sure that \(a+b>ab\), because if \(a=b=0\) then \(a+b=0=ab\) (so in case \(a=b=0\), \(a+b\) is not more than \(ab\) it equals to \(ab\)). Not sufficient.
(2) \(a=-3\) --> \(b=3\) --> \(a+b=0>ab=-9\). Sufficient.
Answer: B.
Hope it's clear.
Bravo. This is the very reason I marked B but was shocked to see that MR people had marked it as D. Thanks Bunuel. You made my day.
Yogesh Agarwal
yogeshagarwala@gmail.com
CONSIDER AWARDING KUDOS IF MY POST HELPS !!!