Math Question Of the Week

Answer: C .

Explanation:

1 alone:

p and q are positive integers, p.q = 225 = 3.3.5.5. Therefore p and q can have any values.

Suppose, p can be 9, and q can be 25 (YES) – q is multiple of 5.

p can be 25 and q can be 9 (NO) – q is not a multiple of 5.

Insufficient

2 alone:

p is a single digit integer and nothing about q.

Insufficient

1 and 2 together:

p.q = 225  and p is a single digit integer.

So p can be 1, 3, 5 or 9 and corresponding values of q are 225, 75, 45, and 25(YES) – in each case ‘q’ will be multiple of 5.

Sufficient

Hence the correct answer C.