Probability Worksheet for Class 8 Maths Olympiad

Maths Olympiad topic 24: Probability basics · Set 214 · 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 odd number? (a) 1/3 (b) 1/6 (c) 1/2 (d) 2/3
2. 2.A bag has 3 red, 5 green and 3 white balls. One ball is taken out without looking. What is the probability that it is not green? (a) 1/3 (b) 5/11 (c) 6/11 (d) 7/11
3. 3.Two dice are rolled together. What is the probability that the two numbers add up to 6? (a) 1/11 (b) 5/36 (c) 5/11 (d) 1/6
4. 4.A fair dice is rolled once. What is the probability of getting a number greater than 2? (a) 5/6 (b) 1/4 (c) 2/3 (d) 1/3
5. 5.A fair dice is rolled once. What is the probability of getting a number greater than 3? (a) 1/3 (b) 2/3 (c) 1/6 (d) 1/2
6. 6.A fair dice is rolled once. What is the probability of getting a multiple of 3? (a) 1/6 (b) 1/3 (c) 1/2 (d) 2/3
7. 7.Three coins are tossed together. What is the probability of getting exactly one head? (a) 1/4 (b) 3/8 (c) 3/5 (d) 5/8
8. 8.A fair dice is rolled once. What is the probability of getting an even number? (a) 2/3 (b) 1/6 (c) 1/2 (d) 1/3
9. 9.A fair dice is rolled once. What is the probability of getting a number greater than 1? (a) 1/5 (b) 1/6 (c) 5/6 (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) 1/3 (b) 2/3 (c) 1/2 (d) 1/4
11. 11.Two coins are tossed together. What is the probability of getting exactly one head? (a) 1/4 (b) 1/3 (c) 1/2 (d) 2/3
12. 12.Two coins are tossed together. What is the probability of getting a head on every coin? (a) 1/4 (b) 1/2 (c) 1/3 (d) 3/4
13. 13.Three coins are tossed together. What is the probability of getting a head on every coin? (a) 1/4 (b) 1/7 (c) 1/8 (d) 7/8
14. 14.Two dice are rolled together. What is the probability that the two numbers add up to 4? (a) 1/12 (b) 1/9 (c) 3/11 (d) 1/11
15. 15.Two coins are tossed together. What is the probability of getting at least one head? (a) 1/4 (b) 1/3 (c) 3/4 (d) 1/2
16. 16.A bag has 5 green, 6 white and 2 yellow balls. One ball is taken out without looking. What is the probability that it is not green? (a) 8/13 (b) 1/3 (c) 9/13 (d) 5/13
17. 17.A bag has 3 red, 4 white and 2 green balls. One ball is taken out without looking. What is the probability that it is red? (a) 4/9 (b) 1/3 (c) 1/2 (d) 2/3
18. 18.Two dice are rolled together. What is the probability that the two numbers add up to 2? (a) 1/11 (b) 1/18 (c) 1/12 (d) 1/36
19. 19.A bag has 7 red, 3 white and 9 green balls. One ball is taken out without looking. What is the probability that it is not red? (a) 13/19 (b) 1/3 (c) 7/19 (d) 12/19
20. 20.A bag has 6 white, 2 red and 6 blue balls. One ball is taken out without looking. What is the probability that it is white? (a) 3/4 (b) 4/7 (c) 3/7 (d) 1/3
21. 21.A bag has 7 white, 8 green and 8 red balls. One ball is taken out without looking. What is the probability that it is white? (a) 7/23 (b) 16/23 (c) 1/3 (d) 7/16
22. 22.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
23. 23.A bag has 3 yellow, 5 blue and 2 green balls. One ball is taken out without looking. What is the probability that it is green? (a) 1/3 (b) 1/5 (c) 1/4 (d) 4/5
24. 24.Two dice are rolled together. What is the probability that the two numbers add up to 3? (a) 2/11 (b) 1/12 (c) 1/11 (d) 1/18
25. 25.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
26. 26.A fair dice is rolled once. What is the probability of getting a factor of 6? (a) 5/6 (b) 1/4 (c) 1/3 (d) 2/3
27. 27.A bag has 2 yellow, 6 green and 2 white balls. One ball is taken out without looking. What is the probability that it is yellow? (a) 4/5 (b) 1/3 (c) 1/4 (d) 1/5
28. 28.A fair dice is rolled once. What is the probability of getting a number greater than 4? (a) 2/3 (b) 1/6 (c) 1/2 (d) 1/3
29. 29.A bag has 5 red, 2 green and 2 blue balls. One ball is taken out without looking. What is the probability that it is not red? (a) 1/3 (b) 4/5 (c) 5/9 (d) 4/9
30. 30.A bag has 5 red, 9 white and 2 blue balls. One ball is taken out without looking. What is the probability that it is not blue? (a) 1/8 (b) 1/3 (c) 7/8 (d) 15/16
31. 31.Two dice are rolled together. What is the probability that the two numbers add up to 9? (a) 5/36 (b) 1/11 (c) 1/9 (d) 4/11
32. 32.A bag has 3 yellow, 8 green and 4 white balls. One ball is taken out without looking. What is the probability that it is green? (a) 1/3 (b) 7/15 (c) 8/15 (d) 3/5
33. 33.A fair dice is rolled once. What is the probability of getting a prime number? (a) 1/2 (b) 2/3 (c) 1/6 (d) 1/3
34. 34.Three coins are tossed together. What is the probability of getting at least one head and at least one tail? (a) 3/4 (b) 3/8 (c) 1/8 (d) 1/4
35. 35.A fair dice is rolled once. What is the probability of getting a number less than 3? (a) 2/3 (b) 1/2 (c) 1/3 (d) 1/6
36. 36.A bag has 9 yellow, 7 white and 2 blue balls. One ball is taken out without looking. What is the probability that it is not blue? (a) 1/3 (b) 8/9 (c) 1/9 (d) 17/18
37. 37.A bag has 3 yellow, 3 red and 4 green balls. One ball is taken out without looking. What is the probability that it is not red? (a) 7/10 (b) 3/10 (c) 1/3 (d) 4/5
38. 38.A bag has 9 blue, 4 green and 6 red balls. One ball is taken out without looking. What is the probability that it is red? (a) 13/19 (b) 6/13 (c) 1/3 (d) 6/19
39. 39.A bag has 9 green, 2 yellow and 2 blue balls. One ball is taken out without looking. What is the probability that it is not yellow? (a) 2/13 (b) 11/13 (c) 1/3 (d) 12/13
40. 40.A fair dice is rolled once. What is the probability of getting a number less than 4? (a) 2/3 (b) 1/6 (c) 1/3 (d) 1/2

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