1. Three letters are written to different persons, and addresses on three envelopes are also written. Without looking at the addresses, the probability that the letters go into right envelopes is

2. If A and B are two events such that P(A⋃B) = 5/6, P(A⋂B) = 1/3, P(B) = ½, then the events A and B are

3. A boy has a box of balls that contains 7 balls of blue color and 4 balls of red color. He takes out 3 balls at random. What is the probability that the balls taken out by the boy are of same color?

4. Anamika carries a bag which contains 50 coins and each coin is marked from 51 to 100. If she picked one coin at random find the probability that the number on the coin is not a prime number.

5. An unbiased dice is rolled. Find the probability of getting a number less than 7 but greater than 2.

6. A man has a box of mangoes that contains 8 mangoes of green color and 10 mangoes of yellow color. He takes out 5 mangoes at random. What is the probability that the mangoes taken out by the man are of same color?

7. A chair has 5 legs. Even if a leg is broken, the chair will stay balanced on remaining 4 legs. The probability that a leg is broken is 2/5. What is the probability that the chair will stay balanced?

8. A bag contains 7 white balls and 4 red balls. Five balls are drawn from it. Find the probability of getting 3 white and 2 red balls.

9. If three dice are thrown simultaneously, then the probability of getting a score of 5 is

10. Stacy has 43 marbles and Ricky has 92 marbles. Ricky gives a random number of marbles to Stacy. What is the probability that both of them will have an even number of marbles now?

11. A box contains 5 black balls, 4 yellow balls and 11 pink balls. A ball is drawn at random from the box. Find the probability that the ball drawn is neither black nor pink.

12. One purse contains a Rs. 1 coin and three 50 p coins, a second purse contains two one rupees and four 50 p coins and a third purse contains three one rupee coins and two 50 p coin. If a coin is taken out of a purse selected at random, find the chance that it is a rupee.

13. There are 12 apples in a bag, out of which 4 are not ripe. If 5 apples are taken out of the bag randomly, what is the probability of selecting only ripen apples?

14. An urn contains 2 red, 3 yellow and 2 blue balls. 2 balls are drawn randomly, find the probability that drawn balls contain no blue balls.

15. A person throws a die two times and gets the sum of the numbers as 5. Calculate the probability that number 3 appeared at least once in the throw.

16. Let A and B be two independent events. The probability that both A and B occur is 1/12 and the probability that neither A nor B occurs is ½. The respective probabilities of A and B are.

17. Two boys are playing a game in which they have to pick balls out of a bag. The bag contains 4 red, 3 green, 2 blue and 5 black balls. If one of the boy draws four balls at random, what is the probability that two are red and two are blue?

18. A bag contains 4 red balls, 6 White balls, 8 Green balls and 10 Black balls. If one ball is drawn at random, find the probability that it is Black.

19. Radha tossed three unbiased coins. What is the probability of getting at least 2 heads?

20. The probability that a number selected at random from the set of numbers {1, 2, 3, 4, ……, 100} is a cube or a square is :

21. A coin is tossed 6 times. The probability of getting Exactly head three times is

22. Two dice are tossed. The probability that the total score is a prime number is :