Probability Worksheet for Class 8 Maths Olympiad

Maths Olympiad topic 24: Probability basics · Set 579 · 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 6 green, 3 blue and 2 red balls. One ball is taken out without looking. What is the probability that it is not green? (a) 5/6 (b) 1/3 (c) 5/11 (d) 6/11
2. 2.Two dice are rolled together. What is the probability that the two numbers add up to 8? (a) 5/36 (b) 5/11 (c) 1/6 (d) 1/11
3. 3.A bag has 3 yellow, 8 green and 3 white balls. One ball is taken out without looking. What is the probability that it is not green? (a) 3/4 (b) 1/3 (c) 3/7 (d) 4/7
4. 4.A bag has 4 red, 8 yellow and 6 blue balls. One ball is taken out without looking. What is the probability that it is red? (a) 2/9 (b) 1/3 (c) 2/7 (d) 7/9
5. 5.Three coins are tossed together. What is the probability of getting exactly one head? (a) 5/8 (b) 1/4 (c) 3/8 (d) 3/5
6. 6.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
7. 7.A fair dice is rolled once. What is the probability of getting a number less than 4? (a) 2/3 (b) 1/3 (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 fair dice is rolled once. What is the probability of getting a prime number? (a) 2/3 (b) 1/3 (c) 1/6 (d) 1/2
10. 10.A fair dice is rolled once. What is the probability of getting an even number? (a) 1/3 (b) 1/6 (c) 2/3 (d) 1/2
11. 11.A fair dice is rolled once. What is the probability of getting a number less than 3? (a) 1/2 (b) 1/3 (c) 2/3 (d) 1/6
12. 12.Two dice are rolled together. What is the probability that the two numbers add up to 12? (a) 1/11 (b) 1/36 (c) 1/12 (d) 1/18
13. 13.A fair dice is rolled once. What is the probability of getting a factor of 6? (a) 2/3 (b) 5/6 (c) 1/4 (d) 1/3
14. 14.Two dice are rolled together. What is the probability that the two numbers add up to 6? (a) 1/11 (b) 5/11 (c) 5/36 (d) 1/6
15. 15.A bag has 3 yellow, 6 red and 2 green balls. One ball is taken out without looking. What is the probability that it is red? (a) 6/11 (b) 5/11 (c) 7/11 (d) 1/3
16. 16.Two dice are rolled together. What is the probability that the two numbers add up to 2? (a) 1/36 (b) 1/18 (c) 1/11 (d) 1/12
17. 17.Two coins are tossed together. What is the probability of getting at least one head? (a) 1/2 (b) 1/4 (c) 1/3 (d) 3/4
18. 18.A fair dice is rolled once. What is the probability of getting a number less than 2? (a) 5/6 (b) 1/5 (c) 1/3 (d) 1/6
19. 19.A bag has 3 red, 7 green and 4 white balls. One ball is taken out without looking. What is the probability that it is green? (a) 4/7 (b) 1/2 (c) 1/3 (d) 1/14
20. 20.Two dice are rolled together. What is the probability that the two numbers add up to 11? (a) 1/12 (b) 1/18 (c) 2/11 (d) 1/11
21. 21.A fair dice is rolled once. What is the probability of getting a multiple of 3? (a) 1/6 (b) 1/2 (c) 1/3 (d) 2/3
22. 22.A fair dice is rolled once. What is the probability of getting an odd number? (a) 1/3 (b) 2/3 (c) 1/6 (d) 1/2
23. 23.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) 1/4 (d) 1/2
24. 24.A bag has 3 red, 7 green and 9 yellow balls. One ball is taken out without looking. What is the probability that it is red? (a) 3/19 (b) 16/19 (c) 1/3 (d) 3/16
25. 25.A bag has 7 green, 3 blue and 8 red balls. One ball is taken out without looking. What is the probability that it is blue? (a) 5/6 (b) 1/5 (c) 1/6 (d) 1/3
26. 26.A bag has 2 yellow, 4 white and 6 blue balls. One ball is taken out without looking. What is the probability that it is not yellow? (a) 5/6 (b) 11/12 (c) 1/6 (d) 1/3
27. 27.Two coins are tossed together. What is the probability of getting a head on every coin? (a) 1/2 (b) 1/4 (c) 1/3 (d) 3/4
28. 28.A bag has 5 blue, 9 green and 4 white balls. One ball is taken out without looking. What is the probability that it is not green? (a) 1/2 (b) 1/18 (c) 5/9 (d) 1/3
29. 29.Two dice are rolled together. What is the probability that the two numbers add up to 3? (a) 1/11 (b) 2/11 (c) 1/18 (d) 1/12
30. 30.A bag has 2 yellow, 5 white and 6 blue balls. One ball is taken out without looking. What is the probability that it is blue? (a) 6/13 (b) 7/13 (c) 6/7 (d) 1/3
31. 31.Three coins are tossed together. What is the probability of getting at least one head and at least one tail? (a) 1/8 (b) 3/4 (c) 1/4 (d) 3/8
32. 32.A bag has 8 yellow, 3 red and 3 green balls. One ball is taken out without looking. What is the probability that it is not red? (a) 3/14 (b) 6/7 (c) 1/3 (d) 11/14
33. 33.A fair dice is rolled once. What is the probability of getting a number greater than 4? (a) 1/2 (b) 1/3 (c) 1/6 (d) 2/3
34. 34.Three coins are tossed together. What is the probability of getting at least one head? (a) 1/4 (b) 3/8 (c) 7/8 (d) 1/8
35. 35.A bag has 6 blue, 3 red and 8 yellow balls. One ball is taken out without looking. What is the probability that it is blue? (a) 1/3 (b) 6/17 (c) 11/17 (d) 6/11
36. 36.A bag has 2 green, 5 red and 3 blue balls. One ball is taken out without looking. What is the probability that it is green? (a) 4/5 (b) 1/3 (c) 1/5 (d) 1/4
37. 37.A bag has 2 blue, 5 yellow and 2 red balls. One ball is taken out without looking. What is the probability that it is red? (a) 2/7 (b) 2/9 (c) 1/3 (d) 7/9
38. 38.Two dice are rolled together. What is the probability that the two numbers add up to 5? (a) 1/11 (b) 5/36 (c) 4/11 (d) 1/9
39. 39.A bag has 3 red, 8 green and 3 blue balls. One ball is taken out without looking. What is the probability that it is green? (a) 3/7 (b) 1/3 (c) 9/14 (d) 4/7
40. 40.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

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