Question

Each of two persons A and B toss three fair coins. The probability that both get the same number of heads is

Solution

Correct option is

5/16

Let X be the number of heads obtained by A and Y be the number of heads obtained by B. Note that both X and Y are binomial variate with parametersn = 3 and P = 1/2.

Probability that both A and B obtain the same number of heads is 

                                         

                                                  

                                                  

SIMILAR QUESTIONS

Q1

If the mean and variance of a binomial variate X are 2 and 1 respectively, then the probability that X takes values at most 3 is

Q2

If two events A and B such that P(A’) = 0.3, P(B) = 0.5 and P(A  B) = 0.3, then  is

Q3

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

Q4

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 two white and one black ball will be drawn is

Q5

There are four machines and it is known that exactly two of them are faulty. They are tested, one by one, in a random order till both the faulty machines are identified. Then the probability that only two tests are needed is

Q6

A group of 2n boys and 2n girls is randomly divided into two equal groups. The probability that each group contains the same number of boys and girls is

Q7

Let A and B be two events such that P(A) = 0.3 and P(A  B) = 0.8. If Aand B are independent events, then P(B) is

Q8

An unbiased dia with faces marked 1, 2, 3, 4, 5 and 6 is rolled four times out of the four faces obtained, the probability that the minimum value is exactly than 2 and the maximum value is exactly 5 is

Q9

A pair of unbiased dice is rolled together till a sum of either 5 or 7 is obtained. The probability that 5 comes before 7 is

Q10

The probability that a student is not a swimmer is 1/5. The probability that out of 5 students exactly 4 is swimmer is