A gambler has one rupee in his pocket. He tosses an unbiased normal coin unless either he is ruined or unless the coin has been tossed for a maximum of five times. If for each head he wins a rupee and for each tail he looses a rupee, then the probability that the gambler is ruined is

A man wins a rupee for head and loses a rupee for tail when coin is tossed. Suppose that he tosses once and quits if he wins but tries once more if he loses on the first toss. Find the probability distribution of the number of rupees the man wins.

A man wins a rupee for head and loses a rupee for tai when coin is tossed.Suppose that he tosses once and quits if he wins but xx once more if he loses on the first toss.Find the probability distribution of the number of rupees the man wins.

A coin is tossed until a head appears or until it has been tossed three times. Given that 'head' does not occur on the first toss, what is the probability that the coin is tossed thrice?

In an exam, 10 questions of true-false type are asked. A student tosses a fair coin to determine his answer to each question. If the coin falls heads, he answers true and if it falls tails, he answers false. Show that the probability that he answers at most 7 questions correctly is 121/128 .

A coin is tossed until a head appears or it has been tossed 3 times. Given that head doesn't appear on the first toss, the probability that coin is tossed 3 times is

A man is know to speak truth 4 out of 5 times. He tossed a coin and reports that it is head. Find the probability that it is actually head.