Let x = number of doublets
∴ Expected value of x will be 0, 1, 2, 3
Set of all doublets available on a pair of dice in a throw = (1,1), (2, 2), (3,3), (4,4), (5, 5), (6, 6)
Number of all possible ways on throwing a pair of dice. = 6 × 6 = 36
∴ Probability of getting a doublets on a pair of dice in a throw = 6/36 = 1/6
∴ Probability of getting a doublets on a pair of dice throw = 1 – 1/6 = 5/6
