# Probability

Subject matter experts of JagranJosh have developed chapter wise practice questions of Class 12th as per the relevancy of the chapter in the CBSE board exam. This practice set contains 10 questions with detailed explanations on “Chapter: Probability” of Mathematics.

• Q1.Value of K for the following probability Distribution is

 X 0 1 2 3 4 5 6 7 P(X) 0 K 2K 2K 3K K2 2 K2 7 K2+K

• Q2.How many times must a fair coin be tossed so that the probability of getting at least one head is more than 80%.

• Q3.In a set of 10 coins , 2 coins are with heads on both the sides.a coin is selected at random from the set and tossed five times.if all the five times, the result was heads, thenthe probability that the selected coin had heads on both the sides is:

• Q4.Two numbers are selected at random ( without replacement) from first six positive integers. let X denote the larger of the two numbers obtained. Find the probability distribution of X. Then the mean of distribution is.

• Q5.The probability of simultaneous occurrence of at least one of two events A and B is p. If the probability that exactly one of A, B occurs is q, then P (A′) + P (B′) = ?