Important question of Probability for Bank PO exam

(1)A box contains 6 black and 8 white balls.One ball is drawn at random.What is the probability that the ball drawn is white?(Asked in Bank Po Exam 2000)

1. 3/44
2. 3/55
3. 52/55
4. 41/44

(2)A bag contains 2 red,3 green and 2 blue balls.Two balls are drawn at random.What is the probability that none of the balls drawn is blue?(Asked in Bank PO Exam 2003)

1. 10/21
2. 11/21
3. 2/7
4. 5/7

(3)In a box,there are 8 red,7 blue and 6 green balls.One ball is picked up randomly.What is the probability that it is neither red nor green? (Asked in Bank Po Exam 2002)

1. 2/3
2. 3/4
3. 7/19
4. 8/21
5. 9/21

(4)A speaks truth in 75% cases and B in 80% cases.In what percentage of cases are they likely to contradict each other,narrating the same incident?(Asked in Bank PO 2000)

1. 5%
2. 15%
3. 35%
4. 45%

(5)A man and his wife appear in an interview for two vacancies in the same post.The probability of husband's selection is (1/7) and the probability of wife's selection is (1/5).What is the probability that only one of them is selected?

1. 4/5
2. 2/7
3. 8/15
4. 4/7

(6)Two dice are tossed.The probability that the total score is a prime number is

1. 1/16
2. 5/12
3. 1/2
4. 7/9

(7)In a class,30% of the students offered English,20% offered Hindi and 10% offered both.If a student is selected at random,what is the probability that he has offered english or hindi?

1. 2/5
2. 3/4
3. 3/5
4. 3/10

(8)A box contains 20 electric bulbs,out of which 4 are defective.Two bulbs are chosen at random from this box.The probability that at least one of these is defective is:

1. 4/19
2. 7/19
3. 12/19
4. 21/95

(9)Four persons are chosen at random from a group of 3 men,2 women and 4 children.The chance that exactly 2 of them are children is:

1. 1/9
2. 1/5
3. 1/12
4. 10/12

(10)In a class,there are 15 boys and 10 girls.Three students are selected at random.The probability that 1 girl and 2 boys are selected is:

1. 21/46
2. 25/117
3. 1/50
4. 3/25

Answers

Question Number	Answer
1	4
2	1
3	4
4	3
5	2
6	2
7	1
8	2
9	4
10	1