Probability Worksheet for Class 8 Maths Olympiad

Maths Olympiad topic 24: Probability basics · Set 101 · 40 questions

How to solve it (Favourable over total): Probability = number of favourable outcomes ÷ total number of equally likely outcomes. List the outcomes: a dice has 6, two coins have 4 (HH, HT, TH, TT), three coins have 8, two dice have 36. Write the answer as a fraction in its lowest terms; a probability is never more than 1.

1. 1.A fair dice is rolled once. What is the probability of getting an odd number? (a) 1/3 (b) 1/6 (c) 1/2 (d) 2/3
2. 2.Two coins are tossed together. What is the probability of getting exactly one head? (a) 2/3 (b) 1/3 (c) 1/2 (d) 1/4
3. 3.A fair dice is rolled once. What is the probability of getting a prime number? (a) 1/6 (b) 1/2 (c) 2/3 (d) 1/3
4. 4.Two dice are rolled together. What is the probability that the two numbers add up to 2? (a) 1/12 (b) 1/18 (c) 1/11 (d) 1/36
5. 5.Two dice are rolled together. What is the probability that the two numbers add up to 3? (a) 1/18 (b) 1/12 (c) 1/11 (d) 2/11
6. 6.A fair dice is rolled once. What is the probability of getting a factor of 6? (a) 2/3 (b) 5/6 (c) 1/4 (d) 1/3
7. 7.A fair dice is rolled once. What is the probability of getting a number less than 4? (a) 2/3 (b) 1/3 (c) 1/2 (d) 1/6
8. 8.A bag has 8 red, 8 green and 5 yellow balls. One ball is taken out without looking. What is the probability that it is yellow? (a) 5/21 (b) 16/21 (c) 1/3 (d) 5/16
9. 9.A bag has 3 white, 3 green and 4 red balls. One ball is taken out without looking. What is the probability that it is white? (a) 1/3 (b) 7/10 (c) 3/10 (d) 3/7
10. 10.Two dice are rolled together. What is the probability that the two numbers add up to 12? (a) 1/12 (b) 1/36 (c) 1/18 (d) 1/11
11. 11.Three coins are tossed together. What is the probability of getting at least one head? (a) 1/4 (b) 7/8 (c) 3/8 (d) 1/8
12. 12.A bag has 6 red, 4 yellow and 2 white balls. One ball is taken out without looking. What is the probability that it is white? (a) 1/3 (b) 1/5 (c) 1/6 (d) 5/6
13. 13.Two dice are rolled together. What is the probability that the two numbers add up to 11? (a) 2/11 (b) 1/11 (c) 1/12 (d) 1/18
14. 14.Two coins are tossed together. What is the probability of getting at least one head and at least one tail? (a) 1/2 (b) 1/3 (c) 1/4 (d) 2/3
15. 15.Two dice are rolled together. What is the probability that the two numbers add up to 5? (a) 4/11 (b) 1/9 (c) 1/11 (d) 5/36
16. 16.Three coins are tossed together. What is the probability of getting at least one head and at least one tail? (a) 1/8 (b) 3/4 (c) 3/8 (d) 1/4
17. 17.A bag has 9 red, 8 blue and 7 yellow balls. One ball is taken out without looking. What is the probability that it is not blue? (a) 1/24 (b) 1/3 (c) 2/3 (d) 17/24
18. 18.A fair dice is rolled once. What is the probability of getting a number greater than 2? (a) 1/3 (b) 1/4 (c) 5/6 (d) 2/3
19. 19.A bag has 6 green, 9 blue and 6 red balls. One ball is taken out without looking. What is the probability that it is blue? (a) 1/3 (b) 3/7 (c) 3/4 (d) 4/7
20. 20.A fair dice is rolled once. What is the probability of getting an even number? (a) 2/3 (b) 1/2 (c) 1/6 (d) 1/3
21. 21.Two dice are rolled together. What is the probability that the two numbers add up to 7? (a) 1/6 (b) 7/36 (c) 1/11 (d) 6/11
22. 22.A bag has 7 blue, 5 yellow and 6 green balls. One ball is taken out without looking. What is the probability that it is green? (a) 1/2 (b) 7/18 (c) 2/3 (d) 1/3
23. 23.Two dice are rolled together. What is the probability that the two numbers add up to 4? (a) 1/12 (b) 1/9 (c) 3/11 (d) 1/11
24. 24.Two dice are rolled together. What is the probability that the two numbers add up to 6? (a) 1/6 (b) 5/11 (c) 5/36 (d) 1/11
25. 25.Two dice are rolled together. What is the probability that the two numbers add up to 10? (a) 1/11 (b) 1/9 (c) 3/11 (d) 1/12
26. 26.Two coins are tossed together. What is the probability of getting a head on every coin? (a) 3/4 (b) 1/4 (c) 1/3 (d) 1/2
27. 27.A fair dice is rolled once. What is the probability of getting a multiple of 3? (a) 1/6 (b) 1/2 (c) 1/3 (d) 2/3
28. 28.A bag has 9 blue, 5 white and 5 red balls. One ball is taken out without looking. What is the probability that it is not white? (a) 5/19 (b) 15/19 (c) 14/19 (d) 1/3
29. 29.Two coins are tossed together. What is the probability of getting at least one head? (a) 3/4 (b) 1/2 (c) 1/4 (d) 1/3
30. 30.A bag has 4 blue, 3 white and 6 yellow balls. One ball is taken out without looking. What is the probability that it is not blue? (a) 4/13 (b) 10/13 (c) 9/13 (d) 1/3
31. 31.A bag has 3 green, 5 white and 8 yellow balls. One ball is taken out without looking. What is the probability that it is not white? (a) 11/16 (b) 5/16 (c) 1/3 (d) 3/4
32. 32.A bag has 3 green, 4 red and 8 yellow balls. One ball is taken out without looking. What is the probability that it is green? (a) 4/5 (b) 1/5 (c) 1/3 (d) 1/4
33. 33.A bag has 2 green, 5 white and 6 yellow balls. One ball is taken out without looking. What is the probability that it is not green? (a) 2/13 (b) 12/13 (c) 1/3 (d) 11/13
34. 34.A bag has 5 red, 4 blue and 4 white balls. One ball is taken out without looking. What is the probability that it is white? (a) 9/13 (b) 1/3 (c) 4/9 (d) 4/13
35. 35.A fair dice is rolled once. What is the probability of getting a number greater than 3? (a) 1/2 (b) 2/3 (c) 1/3 (d) 1/6
36. 36.A bag has 3 yellow, 5 white and 2 green balls. One ball is taken out without looking. What is the probability that it is not yellow? (a) 7/10 (b) 3/10 (c) 1/3 (d) 4/5
37. 37.Two dice are rolled together. What is the probability that the two numbers add up to 9? (a) 1/9 (b) 1/11 (c) 5/36 (d) 4/11
38. 38.A bag has 5 yellow, 2 green and 3 white balls. One ball is taken out without looking. What is the probability that it is green? (a) 1/4 (b) 1/3 (c) 4/5 (d) 1/5
39. 39.Three coins are tossed together. What is the probability of getting exactly one head? (a) 3/8 (b) 5/8 (c) 1/4 (d) 3/5
40. 40.Three coins are tossed together. What is the probability of getting a head on every coin? (a) 1/7 (b) 1/4 (c) 1/8 (d) 7/8

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