Probability Worksheet for Class 8 Maths Olympiad

Maths Olympiad topic 24: Probability basics · Set 121 · 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 9 white, 2 blue and 8 yellow balls. One ball is taken out without looking. What is the probability that it is not yellow? (a) 11/19 (b) 12/19 (c) 8/19 (d) 1/3
2. 2.Two dice are rolled together. What is the probability that the two numbers add up to 11? (a) 2/11 (b) 1/12 (c) 1/18 (d) 1/11
3. 3.Two dice are rolled together. What is the probability that the two numbers add up to 3? (a) 1/11 (b) 1/12 (c) 1/18 (d) 2/11
4. 4.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
5. 5.Two dice are rolled together. What is the probability that the two numbers add up to 5? (a) 5/36 (b) 1/9 (c) 1/11 (d) 4/11
6. 6.A fair dice is rolled once. What is the probability of getting a number greater than 2? (a) 1/3 (b) 5/6 (c) 1/4 (d) 2/3
7. 7.A bag has 6 yellow, 9 blue and 2 white balls. One ball is taken out without looking. What is the probability that it is not yellow? (a) 1/3 (b) 6/17 (c) 12/17 (d) 11/17
8. 8.Three coins are tossed together. What is the probability of getting a head on every coin? (a) 1/7 (b) 1/8 (c) 7/8 (d) 1/4
9. 9.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
10. 10.A bag has 9 red, 2 white and 8 green balls. One ball is taken out without looking. What is the probability that it is white? (a) 2/19 (b) 2/17 (c) 17/19 (d) 1/3
11. 11.Three coins are tossed together. What is the probability of getting at least one head? (a) 7/8 (b) 1/8 (c) 3/8 (d) 1/4
12. 12.Two coins are tossed together. What is the probability of getting a head on every coin? (a) 1/2 (b) 1/3 (c) 1/4 (d) 3/4
13. 13.A bag has 9 blue, 6 red and 9 yellow balls. One ball is taken out without looking. What is the probability that it is not red? (a) 1/3 (b) 3/4 (c) 19/24 (d) 1/4
14. 14.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
15. 15.Two coins are tossed together. What is the probability of getting exactly one head? (a) 2/3 (b) 1/4 (c) 1/2 (d) 1/3
16. 16.A fair dice is rolled once. What is the probability of getting a number less than 4? (a) 1/3 (b) 1/6 (c) 1/2 (d) 2/3
17. 17.A bag has 4 yellow, 4 blue and 3 green balls. One ball is taken out without looking. What is the probability that it is blue? (a) 4/7 (b) 4/11 (c) 1/3 (d) 7/11
18. 18.A bag has 6 green, 2 white and 5 yellow balls. One ball is taken out without looking. What is the probability that it is yellow? (a) 8/13 (b) 5/13 (c) 1/3 (d) 5/8
19. 19.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
20. 20.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
21. 21.Two dice are rolled together. What is the probability that the two numbers add up to 10? (a) 1/11 (b) 3/11 (c) 1/12 (d) 1/9
22. 22.A bag has 9 white, 8 yellow and 9 red balls. One ball is taken out without looking. What is the probability that it is not white? (a) 9/26 (b) 1/3 (c) 9/13 (d) 17/26
23. 23.A bag has 2 white, 5 green and 9 blue balls. One ball is taken out without looking. What is the probability that it is white? (a) 7/8 (b) 1/3 (c) 1/7 (d) 1/8
24. 24.A bag has 7 green, 4 red and 2 white balls. One ball is taken out without looking. What is the probability that it is not green? (a) 1/3 (b) 6/7 (c) 6/13 (d) 7/13
25. 25.A bag has 2 red, 2 blue and 5 yellow balls. One ball is taken out without looking. What is the probability that it is not blue? (a) 1/3 (b) 2/9 (c) 7/9 (d) 8/9
26. 26.A fair dice is rolled once. What is the probability of getting an even number? (a) 1/3 (b) 1/2 (c) 2/3 (d) 1/6
27. 27.Three coins are tossed together. What is the probability of getting exactly one head? (a) 5/8 (b) 3/5 (c) 1/4 (d) 3/8
28. 28.Two dice are rolled together. What is the probability that the two numbers add up to 4? (a) 1/9 (b) 1/11 (c) 3/11 (d) 1/12
29. 29.Two coins are tossed together. What is the probability of getting at least one head and at least one tail? (a) 1/2 (b) 2/3 (c) 1/4 (d) 1/3
30. 30.A bag has 8 green, 6 red and 9 white balls. One ball is taken out without looking. What is the probability that it is red? (a) 6/17 (b) 1/3 (c) 17/23 (d) 6/23
31. 31.A bag has 8 green, 9 yellow and 5 white balls. One ball is taken out without looking. What is the probability that it is green? (a) 7/11 (b) 4/7 (c) 4/11 (d) 1/3
32. 32.A bag has 6 yellow, 9 blue and 3 white balls. One ball is taken out without looking. What is the probability that it is not yellow? (a) 13/18 (b) 1/3 (c) 2/3 (d) 1/18
33. 33.A bag has 5 red, 7 green and 6 blue balls. One ball is taken out without looking. What is the probability that it is red? (a) 5/13 (b) 1/3 (c) 5/18 (d) 13/18
34. 34.Two dice are rolled together. What is the probability that the two numbers add up to 7? (a) 7/36 (b) 6/11 (c) 1/11 (d) 1/6
35. 35.A bag has 3 blue, 2 red and 3 yellow balls. One ball is taken out without looking. What is the probability that it is yellow? (a) 3/5 (b) 5/8 (c) 3/8 (d) 1/3
36. 36.A bag has 9 red, 8 yellow and 6 white balls. One ball is taken out without looking. What is the probability that it is red? (a) 1/3 (b) 9/23 (c) 14/23 (d) 9/14
37. 37.A bag has 4 yellow, 3 red and 2 white balls. One ball is taken out without looking. What is the probability that it is white? (a) 7/9 (b) 2/7 (c) 1/3 (d) 2/9
38. 38.Two dice are rolled together. What is the probability that the two numbers add up to 8? (a) 1/6 (b) 5/36 (c) 5/11 (d) 1/11
39. 39.A bag has 4 red, 4 green and 4 blue balls. One ball is taken out without looking. What is the probability that it is blue? (a) 1/3 (b) 2/3 (c) 1/2 (d) 5/12
40. 40.A fair dice is rolled once. What is the probability of getting a multiple of 3? (a) 2/3 (b) 1/2 (c) 1/6 (d) 1/3

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