Probability Worksheet for Class 8 Maths Olympiad

Maths Olympiad topic 24: Probability basics · Set 199 · 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 2 red, 9 green and 4 white balls. One ball is taken out without looking. What is the probability that it is red? (a) 13/15 (b) 2/13 (c) 1/3 (d) 2/15
2. 2.Two coins are tossed together. What is the probability of getting exactly one head? (a) 1/3 (b) 1/2 (c) 2/3 (d) 1/4
3. 3.A fair dice is rolled once. What is the probability of getting a prime number? (a) 1/6 (b) 2/3 (c) 1/2 (d) 1/3
4. 4.A fair dice is rolled once. What is the probability of getting an odd number? (a) 1/2 (b) 1/3 (c) 1/6 (d) 2/3
5. 5.A fair dice is rolled once. What is the probability of getting a number less than 3? (a) 1/3 (b) 1/6 (c) 2/3 (d) 1/2
6. 6.A fair dice is rolled once. What is the probability of getting an even number? (a) 1/3 (b) 1/6 (c) 1/2 (d) 2/3
7. 7.Two dice are rolled together. What is the probability that the two numbers add up to 11? (a) 1/18 (b) 2/11 (c) 1/12 (d) 1/11
8. 8.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
9. 9.Two dice are rolled together. What is the probability that the two numbers add up to 8? (a) 5/11 (b) 5/36 (c) 1/6 (d) 1/11
10. 10.A bag has 3 red, 2 green and 3 yellow balls. One ball is taken out without looking. What is the probability that it is not red? (a) 3/4 (b) 3/8 (c) 1/3 (d) 5/8
11. 11.Two dice are rolled together. What is the probability that the two numbers add up to 12? (a) 1/18 (b) 1/12 (c) 1/11 (d) 1/36
12. 12.Two dice are rolled together. What is the probability that the two numbers add up to 7? (a) 1/6 (b) 6/11 (c) 7/36 (d) 1/11
13. 13.Two dice are rolled together. What is the probability that the two numbers add up to 10? (a) 3/11 (b) 1/9 (c) 1/11 (d) 1/12
14. 14.A fair dice is rolled once. What is the probability of getting a multiple of 3? (a) 1/2 (b) 1/3 (c) 1/6 (d) 2/3
15. 15.A fair dice is rolled once. What is the probability of getting a factor of 6? (a) 5/6 (b) 1/4 (c) 2/3 (d) 1/3
16. 16.Three coins are tossed together. What is the probability of getting at least one head? (a) 1/8 (b) 3/8 (c) 7/8 (d) 1/4
17. 17.Two coins are tossed together. What is the probability of getting at least one head? (a) 1/3 (b) 3/4 (c) 1/4 (d) 1/2
18. 18.Two dice are rolled together. What is the probability that the two numbers add up to 2? (a) 1/36 (b) 1/12 (c) 1/11 (d) 1/18
19. 19.Two dice are rolled together. What is the probability that the two numbers add up to 3? (a) 2/11 (b) 1/11 (c) 1/12 (d) 1/18
20. 20.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 not blue? (a) 4/5 (b) 3/4 (c) 1/3 (d) 1/4
21. 21.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
22. 22.Three coins are tossed together. What is the probability of getting at least one head and at least one tail? (a) 1/4 (b) 1/8 (c) 3/8 (d) 3/4
23. 23.A bag has 8 red, 7 blue and 2 white balls. One ball is taken out without looking. What is the probability that it is blue? (a) 10/17 (b) 7/10 (c) 1/3 (d) 7/17
24. 24.A bag has 3 white, 4 blue and 6 red balls. One ball is taken out without looking. What is the probability that it is not red? (a) 1/3 (b) 6/13 (c) 8/13 (d) 7/13
25. 25.Two coins are tossed together. What is the probability of getting a head on every coin? (a) 1/3 (b) 3/4 (c) 1/2 (d) 1/4
26. 26.A bag has 9 white, 2 yellow and 3 red balls. One ball is taken out without looking. What is the probability that it is not red? (a) 3/14 (b) 1/3 (c) 11/14 (d) 6/7
27. 27.A bag has 3 red, 5 white and 6 yellow balls. One ball is taken out without looking. What is the probability that it is yellow? (a) 4/7 (b) 1/3 (c) 3/7 (d) 3/4
28. 28.A fair dice is rolled once. What is the probability of getting a number less than 2? (a) 1/6 (b) 1/3 (c) 1/5 (d) 5/6
29. 29.A bag has 9 blue, 5 yellow and 4 red balls. One ball is taken out without looking. What is the probability that it is not yellow? (a) 5/18 (b) 1/3 (c) 7/9 (d) 13/18
30. 30.A bag has 4 red, 8 yellow and 4 green balls. One ball is taken out without looking. What is the probability that it is not red? (a) 1/4 (b) 3/4 (c) 1/3 (d) 13/16
31. 31.A bag has 3 green, 7 yellow and 4 white balls. One ball is taken out without looking. What is the probability that it is not white? (a) 11/14 (b) 5/7 (c) 1/3 (d) 2/7
32. 32.Two coins are tossed together. What is the probability of getting at least one head and at least one tail? (a) 2/3 (b) 1/3 (c) 1/2 (d) 1/4
33. 33.A bag has 4 white, 7 blue and 9 red balls. One ball is taken out without looking. What is the probability that it is blue? (a) 7/20 (b) 13/20 (c) 7/13 (d) 1/3
34. 34.A bag has 8 red, 6 green and 7 yellow balls. One ball is taken out without looking. What is the probability that it is green? (a) 2/5 (b) 1/3 (c) 5/7 (d) 2/7
35. 35.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
36. 36.A bag has 4 white, 8 blue and 4 green balls. One ball is taken out without looking. What is the probability that it is blue? (a) 1/2 (b) 1/3 (c) 1/16 (d) 9/16
37. 37.A bag has 7 blue, 5 red and 8 yellow balls. One ball is taken out without looking. What is the probability that it is not blue? (a) 7/20 (b) 7/10 (c) 13/20 (d) 1/3
38. 38.A bag has 8 blue, 7 red and 2 yellow balls. One ball is taken out without looking. What is the probability that it is not yellow? (a) 2/17 (b) 15/17 (c) 1/3 (d) 16/17
39. 39.A bag has 8 red, 6 green and 6 blue balls. One ball is taken out without looking. What is the probability that it is not green? (a) 3/4 (b) 3/10 (c) 7/10 (d) 1/3
40. 40.A bag has 4 red, 6 yellow and 4 white balls. One ball is taken out without looking. What is the probability that it is not red? (a) 2/7 (b) 11/14 (c) 5/7 (d) 1/3

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