Probability Tes...

A box contains 100 tickets numbered 1, 2,…,100. Two tickets are chosen at random. It is given that the maximum number on the two chosen tickets is not more than 10. The minimum number on them is 5 with probability

A pack of playing cards was found to contain only 51 cards. If the first cards which are examined are all red, then the probability that the missing is black is

If from each of the three boxes containing 3 white and 1 black, 2 white and 2 black, 1 white and 3 black balls, one ball is drawn at random, then the probability that 2 white and 1 black ball will be drawn is

One hundred identical coins each with probability p of showing up heads are tossed once. If 0 < p < 1 and the probability of heads showing on 50 coins is equal to that of heads showing on 51 coins, then the value of p is

A fair coin is tossed n times. Let X be the number of times head is observed. If P(X = 4), P(X = 5) and P(X = 6) are in H.P., then n is equal to

A man takes a step forward with probability 0.4 and backward with probability 0.6. The probability that at the end of eleven steps he is one step away from the starting point is

In a collage of 300 students, every student reads 5 newspapers and every newspaper is read by 60 students. The number of newspaper is