Question

In a single throw of a pair of different dice, what is the probability of getting 

(i) a prime number on each dice ? 

(ii) a total of 9 or 11 ?

Answer 1

(i) Favourable outcomes are (2, 2) (2, 3) (2, 5) (3, 2) (3, 3) (3, 5) (5, 2) (5, 3) (5, 5) i.e 9 outcomes.

P (a prime number on each die) = 9/36 or 1/4

(ii) Favourable outcomes are (3, 6) (4, 5) (5, 4) (6, 3) (5, 6) (6, 5) i. e 6 outcomes

P(a total of 9 or 11) = 6/36 or 1/6