Probability Worksheet for Class 8 Maths Olympiad

Maths Olympiad topic 24: Probability basics · Set 858 · 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 an even number? (a) 1/2 (b) 2/3 (c) 1/6 (d) 1/3
2. 2.Two dice are rolled together. What is the probability that the two numbers add up to 2? (a) 1/18 (b) 1/11 (c) 1/36 (d) 1/12
3. 3.Three coins are tossed together. What is the probability of getting exactly one head? (a) 3/5 (b) 1/4 (c) 3/8 (d) 5/8
4. 4.Two coins are tossed together. What is the probability of getting at least one head? (a) 1/2 (b) 3/4 (c) 1/4 (d) 1/3
5. 5.A bag has 5 yellow, 8 green and 4 red balls. One ball is taken out without looking. What is the probability that it is not green? (a) 1/3 (b) 10/17 (c) 9/17 (d) 8/17
6. 6.Two dice are rolled together. What is the probability that the two numbers add up to 10? (a) 3/11 (b) 1/12 (c) 1/11 (d) 1/9
7. 7.A fair dice is rolled once. What is the probability of getting a prime number? (a) 1/3 (b) 2/3 (c) 1/2 (d) 1/6
8. 8.Two coins are tossed together. What is the probability of getting exactly one head? (a) 1/2 (b) 1/3 (c) 1/4 (d) 2/3
9. 9.A bag has 9 yellow, 2 red and 9 white balls. One ball is taken out without looking. What is the probability that it is white? (a) 1/3 (b) 11/20 (c) 9/11 (d) 9/20
10. 10.A bag has 3 yellow, 2 blue and 7 white balls. One ball is taken out without looking. What is the probability that it is not white? (a) 1/3 (b) 5/12 (c) 7/12 (d) 5/7
11. 11.A bag has 9 green, 6 yellow and 8 red balls. One ball is taken out without looking. What is the probability that it is not yellow? (a) 17/23 (b) 18/23 (c) 1/3 (d) 6/23
12. 12.A bag has 2 white, 9 green and 3 yellow balls. One ball is taken out without looking. What is the probability that it is not green? (a) 5/9 (b) 9/14 (c) 1/3 (d) 5/14
13. 13.A bag has 9 red, 5 green and 4 white balls. One ball is taken out without looking. What is the probability that it is red? (a) 5/9 (b) 1/18 (c) 1/2 (d) 1/3
14. 14.A fair dice is rolled once. What is the probability of getting a number greater than 4? (a) 2/3 (b) 1/6 (c) 1/3 (d) 1/2
15. 15.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
16. 16.A fair dice is rolled once. What is the probability of getting a number less than 2? (a) 1/6 (b) 5/6 (c) 1/5 (d) 1/3
17. 17.A bag has 3 blue, 2 green and 7 white balls. One ball is taken out without looking. What is the probability that it is green? (a) 1/5 (b) 5/6 (c) 1/3 (d) 1/6
18. 18.Two dice are rolled together. What is the probability that the two numbers add up to 5? (a) 1/11 (b) 4/11 (c) 5/36 (d) 1/9
19. 19.Two coins are tossed together. What is the probability of getting at least one head and at least one tail? (a) 2/3 (b) 1/2 (c) 1/3 (d) 1/4
20. 20.A fair dice is rolled once. What is the probability of getting a number greater than 3? (a) 1/2 (b) 1/6 (c) 2/3 (d) 1/3
21. 21.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
22. 22.Two dice are rolled together. What is the probability that the two numbers add up to 8? (a) 5/36 (b) 5/11 (c) 1/11 (d) 1/6
23. 23.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
24. 24.A fair dice is rolled once. What is the probability of getting a factor of 6? (a) 1/4 (b) 2/3 (c) 5/6 (d) 1/3
25. 25.A fair dice is rolled once. What is the probability of getting a number greater than 2? (a) 1/4 (b) 2/3 (c) 1/3 (d) 5/6
26. 26.A bag has 2 yellow, 2 blue and 3 white balls. One ball is taken out without looking. What is the probability that it is not blue? (a) 1/3 (b) 6/7 (c) 2/7 (d) 5/7
27. 27.A bag has 4 red, 4 blue and 4 green balls. One ball is taken out without looking. What is the probability that it is not blue? (a) 1/3 (b) 1/12 (c) 3/4 (d) 2/3
28. 28.A bag has 8 blue, 6 white and 3 green balls. One ball is taken out without looking. What is the probability that it is green? (a) 1/3 (b) 14/17 (c) 3/14 (d) 3/17
29. 29.Two dice are rolled together. What is the probability that the two numbers add up to 12? (a) 1/36 (b) 1/18 (c) 1/12 (d) 1/11
30. 30.Two dice are rolled together. What is the probability that the two numbers add up to 6? (a) 1/6 (b) 5/36 (c) 5/11 (d) 1/11
31. 31.Two dice are rolled together. What is the probability that the two numbers add up to 3? (a) 2/11 (b) 1/12 (c) 1/18 (d) 1/11
32. 32.Three coins are tossed together. What is the probability of getting a head on every coin? (a) 1/7 (b) 7/8 (c) 1/8 (d) 1/4
33. 33.A bag has 5 blue, 4 white and 4 red balls. One ball is taken out without looking. What is the probability that it is not blue? (a) 1/3 (b) 5/13 (c) 9/13 (d) 8/13
34. 34.A bag has 6 green, 3 blue and 9 red balls. One ball is taken out without looking. What is the probability that it is not blue? (a) 8/9 (b) 5/6 (c) 1/3 (d) 1/6
35. 35.Two coins are tossed together. What is the probability of getting a head on every coin? (a) 1/4 (b) 1/3 (c) 1/2 (d) 3/4
36. 36.Two dice are rolled together. What is the probability that the two numbers add up to 11? (a) 1/11 (b) 1/12 (c) 1/18 (d) 2/11
37. 37.Two dice are rolled together. What is the probability that the two numbers add up to 4? (a) 3/11 (b) 1/9 (c) 1/12 (d) 1/11
38. 38.A bag has 7 blue, 4 yellow and 8 red balls. One ball is taken out without looking. What is the probability that it is not yellow? (a) 4/19 (b) 1/3 (c) 16/19 (d) 15/19
39. 39.A bag has 2 white, 4 green and 3 yellow balls. One ball is taken out without looking. What is the probability that it is yellow? (a) 1/3 (b) 1/2 (c) 2/3 (d) 4/9
40. 40.A fair dice is rolled once. What is the probability of getting a number less than 5? (a) 2/3 (b) 1/4 (c) 1/3 (d) 5/6

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