Probability Worksheet for Class 8 Maths Olympiad

Maths Olympiad topic 24: Probability basics · Set 469 · 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 5 green, 3 red and 6 yellow balls. One ball is taken out without looking. What is the probability that it is not green? (a) 9/14 (b) 5/14 (c) 1/3 (d) 5/7
2. 2.A fair dice is rolled once. What is the probability of getting a multiple of 3? (a) 1/3 (b) 2/3 (c) 1/6 (d) 1/2
3. 3.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
4. 4.Two dice are rolled together. What is the probability that the two numbers add up to 10? (a) 1/9 (b) 3/11 (c) 1/11 (d) 1/12
5. 5.Two coins are tossed together. What is the probability of getting a head on every coin? (a) 3/4 (b) 1/2 (c) 1/3 (d) 1/4
6. 6.Two coins are tossed together. What is the probability of getting exactly one head? (a) 1/3 (b) 1/4 (c) 1/2 (d) 2/3
7. 7.A bag has 3 red, 6 green and 2 white balls. One ball is taken out without looking. What is the probability that it is green? (a) 1/3 (b) 7/11 (c) 5/11 (d) 6/11
8. 8.A fair dice is rolled once. What is the probability of getting an even number? (a) 2/3 (b) 1/3 (c) 1/6 (d) 1/2
9. 9.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
10. 10.A bag has 3 blue, 3 red and 7 yellow balls. One ball is taken out without looking. What is the probability that it is not blue? (a) 11/13 (b) 1/3 (c) 10/13 (d) 3/13
11. 11.A bag has 2 yellow, 5 green and 9 blue balls. One ball is taken out without looking. What is the probability that it is not green? (a) 3/4 (b) 1/3 (c) 11/16 (d) 5/16
12. 12.Two coins are tossed together. What is the probability of getting at least one head? (a) 1/2 (b) 1/3 (c) 1/4 (d) 3/4
13. 13.A fair dice is rolled once. What is the probability of getting a prime number? (a) 1/3 (b) 2/3 (c) 1/6 (d) 1/2
14. 14.Three coins are tossed together. What is the probability of getting at least one head and at least one tail? (a) 1/8 (b) 3/8 (c) 3/4 (d) 1/4
15. 15.A bag has 7 green, 6 red and 2 yellow balls. One ball is taken out without looking. What is the probability that it is not yellow? (a) 1/3 (b) 13/15 (c) 14/15 (d) 2/15
16. 16.Two dice are rolled together. What is the probability that the two numbers add up to 2? (a) 1/12 (b) 1/11 (c) 1/18 (d) 1/36
17. 17.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
18. 18.Three coins are tossed together. What is the probability of getting a head on every coin? (a) 1/7 (b) 7/8 (c) 1/4 (d) 1/8
19. 19.A fair dice is rolled once. What is the probability of getting an odd number? (a) 1/6 (b) 1/3 (c) 1/2 (d) 2/3
20. 20.A bag has 4 green, 7 red and 7 yellow balls. One ball is taken out without looking. What is the probability that it is not red? (a) 1/3 (b) 2/3 (c) 11/18 (d) 7/18
21. 21.Three coins are tossed together. What is the probability of getting at least one head? (a) 3/8 (b) 1/8 (c) 7/8 (d) 1/4
22. 22.A bag has 8 blue, 7 yellow and 4 white balls. One ball is taken out without looking. What is the probability that it is yellow? (a) 12/19 (b) 7/12 (c) 7/19 (d) 1/3
23. 23.A bag has 5 green, 3 blue and 7 red balls. One ball is taken out without looking. What is the probability that it is green? (a) 2/3 (b) 1/3 (c) 2/5 (d) 1/2
24. 24.Two dice are rolled together. What is the probability that the two numbers add up to 11? (a) 2/11 (b) 1/18 (c) 1/12 (d) 1/11
25. 25.A bag has 5 green, 7 yellow and 7 blue balls. One ball is taken out without looking. What is the probability that it is not yellow? (a) 1/3 (b) 7/19 (c) 12/19 (d) 13/19
26. 26.A bag has 4 white, 6 red and 4 blue balls. One ball is taken out without looking. What is the probability that it is white? (a) 5/7 (b) 2/7 (c) 1/3 (d) 2/5
27. 27.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
28. 28.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
29. 29.Two dice are rolled together. What is the probability that the two numbers add up to 5? (a) 1/9 (b) 5/36 (c) 1/11 (d) 4/11
30. 30.Two dice are rolled together. What is the probability that the two numbers add up to 7? (a) 1/11 (b) 7/36 (c) 1/6 (d) 6/11
31. 31.A bag has 7 green, 5 blue and 3 yellow balls. One ball is taken out without looking. What is the probability that it is not blue? (a) 1/15 (b) 1/3 (c) 11/15 (d) 2/3
32. 32.Two dice are rolled together. What is the probability that the two numbers add up to 8? (a) 5/11 (b) 1/6 (c) 5/36 (d) 1/11
33. 33.Two dice are rolled together. What is the probability that the two numbers add up to 6? (a) 1/11 (b) 5/11 (c) 1/6 (d) 5/36
34. 34.A bag has 8 red, 3 yellow and 6 blue balls. One ball is taken out without looking. What is the probability that it is not yellow? (a) 14/17 (b) 3/17 (c) 15/17 (d) 1/3
35. 35.Two dice are rolled together. What is the probability that the two numbers add up to 8? (a) 5/36 (b) 1/6 (c) 5/11 (d) 1/11
36. 36.Two dice are rolled together. What is the probability that the two numbers add up to 3? (a) 1/11 (b) 2/11 (c) 1/12 (d) 1/18
37. 37.A bag has 3 white, 4 green and 3 yellow balls. One ball is taken out without looking. What is the probability that it is green? (a) 2/5 (b) 3/5 (c) 1/3 (d) 2/3
38. 38.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
39. 39.A bag has 5 yellow, 6 red and 5 blue balls. One ball is taken out without looking. What is the probability that it is not blue? (a) 1/3 (b) 3/4 (c) 5/16 (d) 11/16
40. 40.A bag has 9 green, 9 white and 3 red balls. One ball is taken out without looking. What is the probability that it is not red? (a) 19/21 (b) 6/7 (c) 1/7 (d) 1/3

Free maths olympiad lessons, practice and worksheets at talentjr.in/maths-olympiad