Question

Which of the following ( 15, 20, 30, 57 ) is the product of exactly three different prime numbers?

Answer 1

30=2*3*5, so it's 30

Explanation:

15=3*5, so it's not 15

20=2*2*5, so it's not 20

30=2*3*5, so it's 30

57=19*3, so it's not 57