The outcomes on rolling a 5-sided die are : {1,2,3,4,5,6}
The factors of these outcomes are:
1 = 1 x 1
2 = 1 x 2
3 = 1 x 3
4 = 2 x 2
5 = 1 x 5
6 = 2 x 3
1 is not a prime number. So the numbers which have 2 prime factors are 4 and 6.
Thus, number of favorable outcomes = 2
The probability of rolling a number with exactly 2 prime factors = 2/6 = 1/3