Probability Worksheet for Class 8 Maths Olympiad

Maths Olympiad topic 24: Probability basics · Set 167 · 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 bag has 9 blue, 4 red and 3 yellow balls. One ball is taken out without looking. What is the probability that it is not yellow? (a) 13/16 (b) 1/3 (c) 7/8 (d) 3/16
2. 2.A fair dice is rolled once. What is the probability of getting an even number? (a) 2/3 (b) 1/2 (c) 1/3 (d) 1/6
3. 3.A fair dice is rolled once. What is the probability of getting a prime number? (a) 1/6 (b) 1/2 (c) 1/3 (d) 2/3
4. 4.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
5. 5.Three coins are tossed together. What is the probability of getting exactly one head? (a) 3/5 (b) 1/4 (c) 5/8 (d) 3/8
6. 6.A fair dice is rolled once. What is the probability of getting a factor of 6? (a) 5/6 (b) 1/3 (c) 2/3 (d) 1/4
7. 7.A fair dice is rolled once. What is the probability of getting a number greater than 2? (a) 1/4 (b) 5/6 (c) 2/3 (d) 1/3
8. 8.Two dice are rolled together. What is the probability that the two numbers add up to 3? (a) 1/12 (b) 1/11 (c) 2/11 (d) 1/18
9. 9.A fair dice is rolled once. What is the probability of getting a multiple of 3? (a) 2/3 (b) 1/6 (c) 1/3 (d) 1/2
10. 10.Two coins are tossed together. What is the probability of getting at least one head and at least one tail? (a) 1/2 (b) 1/4 (c) 2/3 (d) 1/3
11. 11.Three coins are tossed together. What is the probability of getting at least one head? (a) 3/8 (b) 1/4 (c) 1/8 (d) 7/8
12. 12.Two dice are rolled together. What is the probability that the two numbers add up to 4? (a) 3/11 (b) 1/12 (c) 1/9 (d) 1/11
13. 13.Two dice are rolled together. What is the probability that the two numbers add up to 12? (a) 1/12 (b) 1/11 (c) 1/36 (d) 1/18
14. 14.A fair dice is rolled once. What is the probability of getting an odd number? (a) 1/3 (b) 1/2 (c) 2/3 (d) 1/6
15. 15.Two dice are rolled together. What is the probability that the two numbers add up to 9? (a) 1/9 (b) 4/11 (c) 1/11 (d) 5/36
16. 16.A bag has 3 yellow, 8 green and 8 blue balls. One ball is taken out without looking. What is the probability that it is not yellow? (a) 17/19 (b) 16/19 (c) 3/19 (d) 1/3
17. 17.A bag has 5 red, 6 yellow and 8 green balls. One ball is taken out without looking. What is the probability that it is not red? (a) 14/19 (b) 15/19 (c) 1/3 (d) 5/19
18. 18.A bag has 4 yellow, 8 blue and 8 red balls. One ball is taken out without looking. What is the probability that it is blue? (a) 3/5 (b) 2/5 (c) 2/3 (d) 1/3
19. 19.Two dice are rolled together. What is the probability that the two numbers add up to 6? (a) 1/6 (b) 1/11 (c) 5/11 (d) 5/36
20. 20.Three coins are tossed together. What is the probability of getting a head on every coin? (a) 7/8 (b) 1/8 (c) 1/4 (d) 1/7
21. 21.A bag has 7 white, 9 red and 6 yellow balls. One ball is taken out without looking. What is the probability that it is white? (a) 7/22 (b) 15/22 (c) 7/15 (d) 1/3
22. 22.Two dice are rolled together. What is the probability that the two numbers add up to 11? (a) 2/11 (b) 1/18 (c) 1/11 (d) 1/12
23. 23.Two coins are tossed together. What is the probability of getting exactly one head? (a) 2/3 (b) 1/4 (c) 1/2 (d) 1/3
24. 24.A bag has 7 green, 9 red and 4 yellow balls. One ball is taken out without looking. What is the probability that it is yellow? (a) 1/3 (b) 1/5 (c) 1/4 (d) 4/5
25. 25.A fair dice is rolled once. What is the probability of getting a number less than 2? (a) 1/6 (b) 5/6 (c) 1/3 (d) 1/5
26. 26.A fair dice is rolled once. What is the probability of getting a number less than 4? (a) 1/6 (b) 2/3 (c) 1/2 (d) 1/3
27. 27.A bag has 3 green, 7 red and 2 white balls. One ball is taken out without looking. What is the probability that it is not white? (a) 1/3 (b) 1/6 (c) 5/6 (d) 11/12
28. 28.A fair dice is rolled once. What is the probability of getting a number greater than 4? (a) 2/3 (b) 1/2 (c) 1/3 (d) 1/6
29. 29.A bag has 6 blue, 5 white and 7 yellow balls. One ball is taken out without looking. What is the probability that it is yellow? (a) 1/3 (b) 11/18 (c) 7/11 (d) 7/18
30. 30.A fair dice is rolled once. What is the probability of getting a number less than 3? (a) 1/3 (b) 2/3 (c) 1/2 (d) 1/6
31. 31.Two dice are rolled together. What is the probability that the two numbers add up to 10? (a) 1/11 (b) 3/11 (c) 1/12 (d) 1/9
32. 32.A bag has 6 green, 7 white and 9 red balls. One ball is taken out without looking. What is the probability that it is not red? (a) 13/22 (b) 1/3 (c) 9/22 (d) 7/11
33. 33.A bag has 7 green, 6 blue and 2 white balls. One ball is taken out without looking. What is the probability that it is not white? (a) 1/3 (b) 2/15 (c) 13/15 (d) 14/15
34. 34.Two dice are rolled together. What is the probability that the two numbers add up to 8? (a) 1/6 (b) 1/11 (c) 5/36 (d) 5/11
35. 35.A bag has 2 green, 3 red and 8 blue balls. One ball is taken out without looking. What is the probability that it is green? (a) 1/3 (b) 2/13 (c) 2/11 (d) 11/13
36. 36.A bag has 7 green, 4 blue and 2 red balls. One ball is taken out without looking. What is the probability that it is not blue? (a) 4/13 (b) 9/13 (c) 10/13 (d) 1/3
37. 37.A bag has 2 yellow, 5 blue and 9 green balls. One ball is taken out without looking. What is the probability that it is green? (a) 7/16 (b) 1/3 (c) 5/8 (d) 9/16
38. 38.A bag has 7 red, 7 yellow and 7 blue balls. One ball is taken out without looking. What is the probability that it is not blue? (a) 2/3 (b) 1/3 (c) 5/7 (d) 1/21
39. 39.A fair dice is rolled once. What is the probability of getting a number less than 5? (a) 5/6 (b) 1/4 (c) 1/3 (d) 2/3
40. 40.A bag has 6 yellow, 5 blue and 8 red balls. One ball is taken out without looking. What is the probability that it is red? (a) 1/3 (b) 8/11 (c) 8/19 (d) 11/19

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