question_answer 78)

A die is thrown again and again until three sixes are obtained. Find the probability of obtaining the third six in the sixth throw of the die. 

Answer:

The probability of getting 6 in a throw of a             Let x  = number of sixes, then x has the binomial distribution such that required probability       = P(2 sixes in first 5 throws and third six in the sixth throw)         = P(2 sixes in Ist 5 throws) × P (third six in sixth throw).