Q20 of 99 Page 33

A pair of dice is thrown 4 times. If getting a doublet is considered a success, find the probability distribution of a number of successes and hence find its mean.

Throwing doublet: {(1,1),(2,2),(3,3),(4,4),(5,5),(6,6)}


Total outcomes = 6×6 = 36


Let p = probability of success



So, q = 1 - p



Given, n = 4


The required binomial distribution is given by,



Let, X, be the random variable getting doublet, so,













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