Topic: Probability
1. A bag contains 6 black and 8 white balls. One ball is drawn at random. What is the probability that the ball drawn is white?
(a) 3/4 (b) 4/7
(c) 1/8 (d) 3/7
2. A box contains 5 green, 4 yellow and 3 white marbles. Three marbles are drawn at random. What is the probability that all they are not of the same colour?
(a) 3/44 (b) 3/55
3. A bag contains 4 white, 5 red and 6 blue balls. Three balls are drawn at random from the bag. The probability that all of them are red, is:
(a) 1/22 (b) 3/22
(c) 2/91 (d) 2/77
4. A bag contains 6 white and 4 red balls. Three balls are drawn at random. What is the probability that one ball is red and the other two are white?
(a) 1/2 (b) 1/12
(c) 3/10 (d) 7/12
5. 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?
(a) 10/21 (b) 11/21
(c) 2/7 (d) 5/7
6. 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?
(a) 2/3 (b) 3/4
(c) 7/19 (d) 7/21 (e) 9/21
7. A box contains 10 black and 10 white balls. The probability of drawing two balls of the same colour is
(a) 9/19 (b) 9/38
(c) 10/19 (d) 5/19
8. A box contains 4 red balls, 5 green balls and 6 white balls. A ball is drawn at random from the box. What is the probability that the ball drawn is either red or green?
(a) 2/5 (b) 3/5
(c) 1/5 (d) 7/15
9. 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:
(a) 21/46 (b) 25/ 117
(c) 1/50 (d) 3/25
10. 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:
(a) 1/9 (b) 1/5
(c) 1/12 (d) 10/21
Answers
1 | b | 6 | d |
2 | d | 7 | a |
3 | c | 8 | b |
4 | a | 9 | a |
5 | a | 10 | d |
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