Quantcast
Channel: GMAT Club Forum - latest topics
Viewing all articles
Browse latest Browse all 160952

If k is a positive integer, then 20k is divisible by how man

$
0
0
If k is a positive integer, then 20k is divisible by how many different positive integers?

(1) k is prime
(2) k = 7

[Reveal] Spoiler:
Divisible by a positive integer -> factor
No of factors for a number in the form (a^x)(b^y)(c^z) is given by (x+1)(y+1)(z+1)

20k = (2^2)(5^1)(k)

Stmt 1 says k is prime. so 20k = (2^2)(5^1)(k^1). Total # of factors is (2+1)(1+1)(1+1). So sufficient.

Stmy 2 says k = 7 so again Total # of factors is (2+1)(1+1)(1+1). So sufficient.

Hence answer is D, but that is not the OA. What am I missing?

Viewing all articles
Browse latest Browse all 160952

Trending Articles



<script src="https://jsc.adskeeper.com/r/s/rssing.com.1596347.js" async> </script>