Probability Worksheet for Class 8 Maths Olympiad

Maths Olympiad topic 24: Probability basics · Set 138 · 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 7 green, 3 blue and 6 yellow balls. One ball is taken out without looking. What is the probability that it is not yellow? (a) 11/16 (b) 3/8 (c) 1/3 (d) 5/8
2. 2.Two coins are tossed together. What is the probability of getting exactly one head? (a) 1/4 (b) 2/3 (c) 1/2 (d) 1/3
3. 3.Two dice are rolled together. What is the probability that the two numbers add up to 9? (a) 4/11 (b) 5/36 (c) 1/11 (d) 1/9
4. 4.Two dice are rolled together. What is the probability that the two numbers add up to 10? (a) 1/11 (b) 1/12 (c) 3/11 (d) 1/9
5. 5.Two dice are rolled together. What is the probability that the two numbers add up to 3? (a) 2/11 (b) 1/18 (c) 1/12 (d) 1/11
6. 6.Two dice are rolled together. What is the probability that the two numbers add up to 11? (a) 2/11 (b) 1/11 (c) 1/18 (d) 1/12
7. 7.Three coins are tossed together. What is the probability of getting at least one head? (a) 1/4 (b) 7/8 (c) 3/8 (d) 1/8
8. 8.A bag has 8 yellow, 9 white and 8 blue balls. One ball is taken out without looking. What is the probability that it is not yellow? (a) 17/25 (b) 1/3 (c) 8/25 (d) 18/25
9. 9.A fair dice is rolled once. What is the probability of getting a number less than 4? (a) 1/2 (b) 1/6 (c) 2/3 (d) 1/3
10. 10.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) 1/2 (d) 1/3
11. 11.A fair dice is rolled once. What is the probability of getting a number less than 3? (a) 2/3 (b) 1/3 (c) 1/2 (d) 1/6
12. 12.Two coins are tossed together. What is the probability of getting at least one head? (a) 1/3 (b) 1/2 (c) 1/4 (d) 3/4
13. 13.A bag has 3 red, 4 white and 9 yellow balls. One ball is taken out without looking. What is the probability that it is not red? (a) 1/3 (b) 3/16 (c) 13/16 (d) 7/8
14. 14.A bag has 6 white, 9 red and 7 green balls. One ball is taken out without looking. What is the probability that it is white? (a) 3/8 (b) 1/3 (c) 3/11 (d) 8/11
15. 15.A fair dice is rolled once. What is the probability of getting a number greater than 1? (a) 5/6 (b) 1/5 (c) 1/3 (d) 1/6
16. 16.A bag has 6 white, 5 blue and 3 red balls. One ball is taken out without looking. What is the probability that it is blue? (a) 9/14 (b) 5/14 (c) 5/9 (d) 1/3
17. 17.Two dice are rolled together. What is the probability that the two numbers add up to 7? (a) 6/11 (b) 1/11 (c) 7/36 (d) 1/6
18. 18.A bag has 5 yellow, 6 red and 4 white balls. One ball is taken out without looking. What is the probability that it is white? (a) 1/3 (b) 4/15 (c) 4/11 (d) 11/15
19. 19.A fair dice is rolled once. What is the probability of getting a prime number? (a) 1/3 (b) 1/6 (c) 1/2 (d) 2/3
20. 20.Two coins are tossed together. What is the probability of getting a head on every coin? (a) 1/3 (b) 3/4 (c) 1/4 (d) 1/2
21. 21.A bag has 3 red, 6 blue and 7 green balls. One ball is taken out without looking. What is the probability that it is not red? (a) 13/16 (b) 1/3 (c) 3/16 (d) 7/8
22. 22.A bag has 2 yellow, 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) 2/11 (c) 9/11 (d) 10/11
23. 23.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
24. 24.Two dice are rolled together. What is the probability that the two numbers add up to 12? (a) 1/11 (b) 1/12 (c) 1/36 (d) 1/18
25. 25.A fair dice is rolled once. What is the probability of getting an odd number? (a) 1/3 (b) 1/6 (c) 2/3 (d) 1/2
26. 26.A fair dice is rolled once. What is the probability of getting a multiple of 3? (a) 1/6 (b) 1/2 (c) 2/3 (d) 1/3
27. 27.A bag has 8 white, 6 yellow and 6 red balls. One ball is taken out without looking. What is the probability that it is white? (a) 2/3 (b) 3/5 (c) 2/5 (d) 1/3
28. 28.A fair dice is rolled once. What is the probability of getting a factor of 6? (a) 2/3 (b) 1/3 (c) 1/4 (d) 5/6
29. 29.A bag has 2 yellow, 8 green and 9 blue balls. One ball is taken out without looking. What is the probability that it is yellow? (a) 1/3 (b) 2/19 (c) 2/17 (d) 17/19
30. 30.Two dice are rolled together. What is the probability that the two numbers add up to 5? (a) 5/36 (b) 1/11 (c) 1/9 (d) 4/11
31. 31.Two dice are rolled together. What is the probability that the two numbers add up to 8? (a) 5/11 (b) 5/36 (c) 1/11 (d) 1/6
32. 32.Two dice are rolled together. What is the probability that the two numbers add up to 2? (a) 1/11 (b) 1/36 (c) 1/18 (d) 1/12
33. 33.A fair dice is rolled once. What is the probability of getting a number less than 2? (a) 1/6 (b) 1/5 (c) 1/3 (d) 5/6
34. 34.A bag has 8 green, 4 red and 6 yellow balls. One ball is taken out without looking. What is the probability that it is not red? (a) 1/3 (b) 2/9 (c) 7/9 (d) 5/6
35. 35.Two dice are rolled together. What is the probability that the two numbers add up to 4? (a) 1/9 (b) 1/12 (c) 1/11 (d) 3/11
36. 36.Three coins are tossed together. What is the probability of getting exactly one head? (a) 3/5 (b) 3/8 (c) 5/8 (d) 1/4
37. 37.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
38. 38.A bag has 2 blue, 2 green and 7 white balls. One ball is taken out without looking. What is the probability that it is green? (a) 2/9 (b) 9/11 (c) 1/3 (d) 2/11
39. 39.A fair dice is rolled once. What is the probability of getting a number greater than 4? (a) 2/3 (b) 1/3 (c) 1/2 (d) 1/6
40. 40.A bag has 6 white, 8 green and 5 yellow balls. One ball is taken out without looking. What is the probability that it is not yellow? (a) 1/3 (b) 14/19 (c) 5/19 (d) 15/19

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