Probability Q9

9.How many factors of 25*36*52 are perfect squares?

	A.	20
	B.	24
	C.	30
	D.	36

Answer – (B)

Solution:

Any factor of this number should be of the form 2a*3b*5c.
For the factor to be a perfect square a, b, c have to be even.
a can take values 0, 2, 4. b can take values 0,2, 4, 6 and c can take values 0,2.

Total number of perfect squares =3*4*2= 24