multiple of 5 with p and q

This topic has expert replies
Senior | Next Rank: 100 Posts
Posts: 85
Joined: Mon Dec 08, 2008 12:09 am

multiple of 5 with p and q

by tj123 » Mon Jun 01, 2009 9:45 pm
If n is a multiple of 5 and n = p^2q, where p and q are prime numbers, which of the following must be a multiple of 25?

a) p^2
b)q^2
c) pq
d) p^2q^2
e)p^3q

OA d

[spoiler] I chose n = 50, p=5, q=2. then i just went and plugged in numbers and chose e since it worked. My question is how do you know what values of p and q to choose since there are many possibilities here.[/spoiler]

Master | Next Rank: 500 Posts
Posts: 139
Joined: Wed Oct 22, 2008 4:36 am
Thanked: 17 times