Data Sufficiency

K is a set of integers such that if the integer r is in K, then r + 1 is also in K. Is 100 in K?

(1) 50 is in K.
(2) 150 is in K.


Can anyone help pls...?

IMO A

Q says that is r is in set K then r+1 will be in K

Stmt 1 - 50 is in K. Then 51 will be in K. 52 will be in K. So on and so forth... 100 will be in K too

Stmt 2 - 150 is in K. The Q does not say if r is in K, r-1 is in K or not.

I agree with Kajcha ans should be A

Stmt 1 - same as Kajcha explained

Stmt 2 - 150 is in K then 151 must be in K ... hence 100 is not in K, this is possible if 150 is the first integer in the set or basically the set begins from 101.

wheras if the set starts from an integer less than 150 and 100 then 100 will also be there in the set & so will be 150

hence not SUFF

Thanks samir, stmt 2 is better explained that way...

Thank you both for explanation- and you're right the answer is A.