Probability Tes...

4 boys and 2 girls occupy seats in a row at random. Then, the probability that the two girls occupy seats side by side is

A fair coin is tossed 100 times the probability of getting tails an odd number of time is

Out of 3n consecutive natural numbers, 3 natural numbers are chosen at random without replacement. The probability that the sum of the chosen numbers is divisible by 3, is

From a group of 8 boys and 3 girls, a committee of 5 members to be formed. Find the probability that 2 particular girls are included in the committee.

The probability that the three cards drawn from a pack of 52 cards, are all black, is

A determinant of second order is made with the elements 0 and 1. What is the probability that the determinant is positive ?

The probability of choosing randomly a number c from the set {l, 2, 3, ... , 9} such that the quadratic equation x² + 4x + c = 0 has real roots, is

Let S be the sample space of the random experiment of throwing simultaneously two unbiased dice with. six faces (numbered 1 to 6) and E_k = {(a, b) ϵ S : ab = k} for k ≥ 1. If p_k = P(E_k) for k ≥ 1, then the correct among the following is

Three letters, to each of which corresponds an envelope, are placed in the envelopes at random. The probability that all the letters are not placed in the right envelopes, is

The odds against a certain event are 5 : 2 and the odds in favour of another independent event are 6 : 5. The probability that atleast one of the events will happen is