Question

Which number is a factor of 20 and also a prime number?

A.
4


B.
5


C.
7


D.


10

Answer 1

The answer is 5 because, 20= 5*4 then 4= 2*2, from these options 5 is the answer

Answer 2

20 = 2 x 2 x 5, which can also be written 20 = 2² x 5
thus B is your Answer.