Probability Tes...

At a telephone enquiry system the number of phone calls regarding relevant enquiry follow Poisson distribution with an average of 5 phone calls during 10 minute time intervals. The probability that there is at the most one phone call during a 10 minutes time period is

Six boys and six girls sit in a row. What is the probability that the boys and girls sit alternatively

Cards are drawn one by one at random from a well shuffled full pack of 52 cards until two aces are obtained for the first time. If N is the number of cards required to be drawn, then P_r {N = n}, where 2 ≤ n ≤ 50, is

Let X be a set containing n elements. If two subsets A and B of X picked at random, the probability that A and B have the same number of elements, is

If three dice at thrown simultaneously, then the probability of getting a score of 7 is

Seven white balls and three black balls are randomly places in a row. The probability that no two black balls are placed adjacently equals

The probability of happening and event A is 0.5 and that of B is 0.3. If A and B are mutually exclusive events, then the probability of happening neither A nor B is