A pair of dice is thrown 4 times. If getting a doublet is considered a success, find the probability of two successes.


We know that the repeated tosses of a pair of dice are known as Bernouli trials.

Let the number of times of getting doublets in an experiment of throwing two dice simultaneously four times be x.





Thus, P(X = x) = nCxqn-xpx , where x = 0, 1, 2, …n


= 4Cx (5/6)4-x(1/6)x


= 4Cx (54-x/66)


Hence, Probability of getting 2 successes = P(X = 2)


= 4C2(54-2/64)





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