Probability Worksheet for Class 8 Maths Olympiad

Maths Olympiad topic 24: Probability basics · Set 335 · 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.Two dice are rolled together. What is the probability that the two numbers add up to 7? (a) 6/11 (b) 7/36 (c) 1/6 (d) 1/11
2. 2.Two dice are rolled together. What is the probability that the two numbers add up to 9? (a) 5/36 (b) 1/9 (c) 4/11 (d) 1/11
3. 3.Three coins are tossed together. What is the probability of getting a head on every coin? (a) 1/4 (b) 1/7 (c) 7/8 (d) 1/8
4. 4.A fair dice is rolled once. What is the probability of getting an even number? (a) 1/2 (b) 1/6 (c) 1/3 (d) 2/3
5. 5.Three coins are tossed together. What is the probability of getting exactly one head? (a) 5/8 (b) 3/8 (c) 3/5 (d) 1/4
6. 6.Two coins are tossed together. What is the probability of getting at least one head? (a) 1/3 (b) 1/2 (c) 3/4 (d) 1/4
7. 7.A bag has 8 blue, 7 green and 6 yellow balls. One ball is taken out without looking. What is the probability that it is not blue? (a) 2/3 (b) 1/3 (c) 13/21 (d) 8/21
8. 8.A fair dice is rolled once. What is the probability of getting a number greater than 4? (a) 1/3 (b) 2/3 (c) 1/6 (d) 1/2
9. 9.Two coins are tossed together. What is the probability of getting exactly one head? (a) 1/4 (b) 1/3 (c) 1/2 (d) 2/3
10. 10.A fair dice is rolled once. What is the probability of getting a number greater than 2? (a) 5/6 (b) 1/3 (c) 1/4 (d) 2/3
11. 11.A bag has 3 red, 3 white and 9 green balls. One ball is taken out without looking. What is the probability that it is white? (a) 1/5 (b) 1/4 (c) 4/5 (d) 1/3
12. 12.A bag has 9 blue, 2 white and 3 green balls. One ball is taken out without looking. What is the probability that it is not green? (a) 3/14 (b) 11/14 (c) 1/3 (d) 6/7
13. 13.Three coins are tossed together. What is the probability of getting at least one head? (a) 3/8 (b) 7/8 (c) 1/8 (d) 1/4
14. 14.A bag has 7 yellow, 3 white and 9 green balls. One ball is taken out without looking. What is the probability that it is not yellow? (a) 13/19 (b) 12/19 (c) 1/3 (d) 7/19
15. 15.Two dice are rolled together. What is the probability that the two numbers add up to 11? (a) 1/18 (b) 1/12 (c) 1/11 (d) 2/11
16. 16.A fair dice is rolled once. What is the probability of getting a prime number? (a) 2/3 (b) 1/2 (c) 1/3 (d) 1/6
17. 17.Two dice are rolled together. What is the probability that the two numbers add up to 10? (a) 1/11 (b) 3/11 (c) 1/9 (d) 1/12
18. 18.Two dice are rolled together. What is the probability that the two numbers add up to 8? (a) 1/6 (b) 5/36 (c) 5/11 (d) 1/11
19. 19.Two dice are rolled together. What is the probability that the two numbers add up to 12? (a) 1/18 (b) 1/11 (c) 1/12 (d) 1/36
20. 20.A bag has 4 yellow, 4 red and 8 white balls. One ball is taken out without looking. What is the probability that it is not white? (a) 1/3 (b) 1/2 (c) 9/16 (d) 1/16
21. 21.A fair dice is rolled once. What is the probability of getting a number less than 4? (a) 2/3 (b) 1/6 (c) 1/2 (d) 1/3
22. 22.A fair dice is rolled once. What is the probability of getting a number greater than 3? (a) 1/3 (b) 1/6 (c) 2/3 (d) 1/2
23. 23.A fair dice is rolled once. What is the probability of getting a factor of 6? (a) 2/3 (b) 1/4 (c) 5/6 (d) 1/3
24. 24.A bag has 2 blue, 2 yellow and 3 red balls. One ball is taken out without looking. What is the probability that it is yellow? (a) 5/7 (b) 2/5 (c) 2/7 (d) 1/3
25. 25.A bag has 9 yellow, 2 white and 3 blue balls. One ball is taken out without looking. What is the probability that it is not yellow? (a) 9/14 (b) 5/14 (c) 5/9 (d) 1/3
26. 26.Two coins are tossed together. What is the probability of getting a head on every coin? (a) 3/4 (b) 1/3 (c) 1/4 (d) 1/2
27. 27.Two dice are rolled together. What is the probability that the two numbers add up to 3? (a) 2/11 (b) 1/11 (c) 1/18 (d) 1/12
28. 28.Three coins are tossed together. What is the probability of getting at least one head and at least one tail? (a) 1/4 (b) 3/4 (c) 1/8 (d) 3/8
29. 29.A bag has 3 blue, 5 yellow and 3 white balls. One ball is taken out without looking. What is the probability that it is not blue? (a) 8/11 (b) 3/11 (c) 9/11 (d) 1/3
30. 30.A fair dice is rolled once. What is the probability of getting a number greater than 1? (a) 1/3 (b) 1/6 (c) 5/6 (d) 1/5
31. 31.A bag has 2 yellow, 9 green and 2 white balls. One ball is taken out without looking. What is the probability that it is yellow? (a) 11/13 (b) 2/11 (c) 1/3 (d) 2/13
32. 32.A bag has 5 red, 2 green and 3 white balls. One ball is taken out without looking. What is the probability that it is not green? (a) 9/10 (b) 4/5 (c) 1/5 (d) 1/3
33. 33.A bag has 3 red, 2 yellow and 4 green balls. One ball is taken out without looking. What is the probability that it is not red? (a) 7/9 (b) 1/9 (c) 2/3 (d) 1/3
34. 34.Two coins are tossed together. What is the probability of getting at least one head and at least one tail? (a) 2/3 (b) 1/4 (c) 1/3 (d) 1/2
35. 35.Two dice are rolled together. What is the probability that the two numbers add up to 4? (a) 1/11 (b) 3/11 (c) 1/12 (d) 1/9
36. 36.A bag has 5 red, 7 white and 6 green balls. One ball is taken out without looking. What is the probability that it is green? (a) 7/18 (b) 2/3 (c) 1/3 (d) 1/2
37. 37.A bag has 5 white, 2 red and 7 green balls. One ball is taken out without looking. What is the probability that it is white? (a) 9/14 (b) 5/9 (c) 1/3 (d) 5/14
38. 38.A fair dice is rolled once. What is the probability of getting a multiple of 3? (a) 1/6 (b) 2/3 (c) 1/3 (d) 1/2
39. 39.A bag has 4 green, 5 yellow and 4 white balls. One ball is taken out without looking. What is the probability that it is not white? (a) 10/13 (b) 4/13 (c) 1/3 (d) 9/13
40. 40.A bag has 8 blue, 7 white and 6 green balls. One ball is taken out without looking. What is the probability that it is not blue? (a) 1/3 (b) 8/21 (c) 13/21 (d) 2/3

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