Data Sufficiency

please explain how to solve this one?
my method..
take 1. since 1/(k-1) > 0, k-1 should be positive.
therefore, k-1 < 1
hence, k < 2 insuff.

take 2. since 1/(k+2) > 0 , k+1 should be positive.
therefore, k+1 < 1
hence k<0 suff.

hence B..
please lemme know what i did wrong??

ketkoag wrote:please explain how to solve this one?
my method..
take 1. since 1/(k-1) > 0, k-1 should be positive.
therefore, k-1 < 1
hence, k < 2 insuff.

take 2. since 1/(k+2) > 0 , k+1 should be positive.
therefore, k+1 < 1
hence k<0 suff.

hence B..
please lemme know what i did wrong??

Were looking for:

k > 0

For Statement #1
1/(k-1) > 0 for all values of k > 1

A definitive Yes

For Statement #2

1/K+1 > 0

Works for K > -1

InSuff

Couldn't k be a fraction. If k = -1/2 than adding 1 will make 1/(k+1) > 0 even though 1/k < 0. Looks like you changed the direction of the inequality. I think it should read:

1/(k+1) > 0
k+1 should be positive.
therefore, k+1 > 0
hence k>-1

Same issue with 1 as well.

Otherwise I think your setup is fine.