gmat prep - inequality

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gmat prep - inequality

by vkb16 » Mon Oct 26, 2009 1:06 am
If k # 0,1,or -1, is 1/k>0?

I 1/(k-1) > 0
II 1/(k+1) > 0

OA is A

But I think its D
IMO, the only possible values for K by st II are >1

please help me solve this problem!!

thanks
Source: — Data Sufficiency |

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by italian7745 » Mon Oct 26, 2009 1:34 am
For Stem II :-

Consider K=-0.5 which means

= 1 /-0.5 + 1
= 1/0.5
= 2

in that case 1/-0.5 <0

Now if k=0.5

1/k > 0 ...

So insufficient...

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by jaspreet_takhar » Mon Oct 26, 2009 1:48 am
if 1/(k-1)>0, then k-1>0
i:e k>1 which makes 1/k>0, so sufficient

if 1/(k+1)>0, then k+1>0
i:e k>-1
which leads to 1/k<0 for -1<k<0 & 1/k>0 for k>0 , so insufficient

Answer - A