21 set 18

radhika1306 · Posted: Thu Aug 30, 2007 8:55 am Post subject: 21 set 18

18. If K is a positive integer, is K the square of an integer?
(1) K is divisible by 4
(2) K is divisible by exactly 4 different prime numbers

(A) Statement (1) ALONE is sufficient, but statement (2) alone is not sufficient.
(B) Statement (2) ALONE is sufficient, but statement (1) alone is not sufficient.
(C) BOTH statements TOGETHER are sufficient, but NEITHER statement ALONE is sufficient.

kajcha · Posted: Thu Aug 30, 2007 10:16 am Post subject:

IMO E

radhika1306 · Posted: Thu Aug 30, 2007 12:59 pm Post subject:

can u explain

ratindasgupta · Posted: Thu Aug 30, 2007 1:04 pm Post subject: Re: 21 set 18

kajcha · Posted: Thu Aug 30, 2007 1:14 pm Post subject:

Stmt 1 - K is divisble by 4.. so nos can be 4, 8, 12... not all numbers are sq of an int - NOT SUFF

Stmt 2 - k is divisble be 4 prime nos - so if we choose no as 2*3*5*7 = 210.. this is divisble be 4 prime nos but not a square of an int.. however, we can have a no 210^2 - divisible by 2,3, 5, 7 but also square.. NOT SUFF

Together - NOT SUFF

So E