Probability Worksheet for Class 8 Maths Olympiad

Maths Olympiad topic 24: Probability basics · Set 59 · 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 a factor of 6? (a) 2/3 (b) 1/3 (c) 5/6 (d) 1/4
2. 2.A bag has 3 white, 6 red and 9 yellow balls. One ball is taken out without looking. What is the probability that it is red? (a) 1/3 (b) 7/18 (c) 2/3 (d) 1/2
3. 3.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
4. 4.A fair dice is rolled once. What is the probability of getting a number less than 3? (a) 1/6 (b) 2/3 (c) 1/2 (d) 1/3
5. 5.A bag has 2 yellow, 3 white and 8 blue balls. One ball is taken out without looking. What is the probability that it is not white? (a) 10/13 (b) 1/3 (c) 11/13 (d) 3/13
6. 6.A bag has 4 red, 3 blue and 9 yellow balls. One ball is taken out without looking. What is the probability that it is red? (a) 5/16 (b) 1/4 (c) 3/4 (d) 1/3
7. 7.A bag has 9 white, 7 green and 9 yellow balls. One ball is taken out without looking. What is the probability that it is white? (a) 16/25 (b) 1/3 (c) 9/25 (d) 9/16
8. 8.Two dice are rolled together. What is the probability that the two numbers add up to 11? (a) 1/11 (b) 1/18 (c) 2/11 (d) 1/12
9. 9.A bag has 6 blue, 6 white and 2 yellow balls. One ball is taken out without looking. What is the probability that it is not white? (a) 1/3 (b) 4/7 (c) 9/14 (d) 3/7
10. 10.A fair dice is rolled once. What is the probability of getting a number greater than 4? (a) 1/6 (b) 1/3 (c) 2/3 (d) 1/2
11. 11.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
12. 12.A bag has 7 white, 8 red and 5 blue balls. One ball is taken out without looking. What is the probability that it is white? (a) 1/3 (b) 7/13 (c) 13/20 (d) 7/20
13. 13.Three coins are tossed together. What is the probability of getting exactly one head? (a) 1/4 (b) 5/8 (c) 3/5 (d) 3/8
14. 14.Two dice are rolled together. What is the probability that the two numbers add up to 2? (a) 1/12 (b) 1/36 (c) 1/11 (d) 1/18
15. 15.A bag has 5 red, 6 green and 4 blue balls. One ball is taken out without looking. What is the probability that it is not red? (a) 1/15 (b) 11/15 (c) 1/3 (d) 2/3
16. 16.Two coins are tossed together. What is the probability of getting a head on every coin? (a) 1/4 (b) 3/4 (c) 1/2 (d) 1/3
17. 17.A fair dice is rolled once. What is the probability of getting an odd number? (a) 2/3 (b) 1/6 (c) 1/3 (d) 1/2
18. 18.Two dice are rolled together. What is the probability that the two numbers add up to 9? (a) 5/36 (b) 1/9 (c) 1/11 (d) 4/11
19. 19.Two dice are rolled together. What is the probability that the two numbers add up to 3? (a) 1/18 (b) 1/11 (c) 2/11 (d) 1/12
20. 20.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
21. 21.A bag has 8 green, 9 blue and 9 red balls. One ball is taken out without looking. What is the probability that it is green? (a) 4/9 (b) 1/3 (c) 4/13 (d) 9/13
22. 22.A bag has 7 green, 8 yellow and 4 blue balls. One ball is taken out without looking. What is the probability that it is not green? (a) 7/19 (b) 13/19 (c) 1/3 (d) 12/19
23. 23.A bag has 5 white, 4 red and 7 blue balls. One ball is taken out without looking. What is the probability that it is blue? (a) 7/9 (b) 9/16 (c) 1/3 (d) 7/16
24. 24.Two dice are rolled together. What is the probability that the two numbers add up to 8? (a) 1/6 (b) 5/11 (c) 1/11 (d) 5/36
25. 25.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
26. 26.A fair dice is rolled once. What is the probability of getting a number greater than 3? (a) 2/3 (b) 1/2 (c) 1/6 (d) 1/3
27. 27.A fair dice is rolled once. What is the probability of getting a multiple of 3? (a) 2/3 (b) 1/2 (c) 1/6 (d) 1/3
28. 28.A bag has 9 red, 4 white and 3 blue balls. One ball is taken out without looking. What is the probability that it is not white? (a) 1/4 (b) 3/4 (c) 1/3 (d) 13/16
29. 29.A fair dice is rolled once. What is the probability of getting a prime number? (a) 1/6 (b) 1/3 (c) 1/2 (d) 2/3
30. 30.A bag has 5 white, 4 green and 5 red balls. One ball is taken out without looking. What is the probability that it is white? (a) 5/9 (b) 5/14 (c) 1/3 (d) 9/14
31. 31.Two coins are tossed together. What is the probability of getting exactly one head? (a) 1/3 (b) 2/3 (c) 1/2 (d) 1/4
32. 32.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
33. 33.A fair dice is rolled once. What is the probability of getting a number less than 2? (a) 1/3 (b) 1/5 (c) 5/6 (d) 1/6
34. 34.A bag has 3 yellow, 6 blue and 6 red balls. One ball is taken out without looking. What is the probability that it is not yellow? (a) 1/5 (b) 13/15 (c) 1/3 (d) 4/5
35. 35.A bag has 3 yellow, 7 red and 3 white balls. One ball is taken out without looking. What is the probability that it is white? (a) 3/13 (b) 1/3 (c) 3/10 (d) 10/13
36. 36.Two dice are rolled together. What is the probability that the two numbers add up to 6? (a) 5/11 (b) 1/6 (c) 5/36 (d) 1/11
37. 37.A fair dice is rolled once. What is the probability of getting a number less than 5? (a) 1/4 (b) 1/3 (c) 5/6 (d) 2/3
38. 38.A bag has 8 green, 2 white and 9 yellow balls. One ball is taken out without looking. What is the probability that it is green? (a) 11/19 (b) 1/3 (c) 8/11 (d) 8/19
39. 39.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
40. 40.Two coins are tossed together. What is the probability of getting at least one head? (a) 1/2 (b) 1/3 (c) 3/4 (d) 1/4

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