ricaototti wrote:What is the greatest possible common divisor of two diff positive
integers which are less than 144
1 143
2 142
3 72
4 71
5 12

Guys, what is the thought process behind the answer. It sounds stupid but I have problems with LCM and GCF on GMAT.

Thanks!

I go with D 71.

u need to understand the concept of GCD ..
GCD of two non-zero integers, is the largest positive integer that divides both numbers without remainder

do it by elimination

A.143 . for it to be 143 the next number shud be 143*2 = 286..
but our condition is both shud <144

B. 142 same as A

C 72.. the next number will be 144.. shud be <144

D 71 . the next number is 142 which < 144 ..

thus its D.

hope it helps.... do let us know the OA

OA is indeed D.

Thanks for the explanation.