Probability Worksheet for Class 8 Maths Olympiad

Maths Olympiad topic 24: Probability basics · Set 225 · 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.Two dice are rolled together. What is the probability that the two numbers add up to 9? (a) 4/11 (b) 1/11 (c) 1/9 (d) 5/36
2. 2.A fair dice is rolled once. What is the probability of getting a number greater than 3? (a) 1/6 (b) 1/2 (c) 2/3 (d) 1/3
3. 3.A bag has 7 red, 3 yellow and 9 blue balls. One ball is taken out without looking. What is the probability that it is yellow? (a) 1/3 (b) 3/16 (c) 16/19 (d) 3/19
4. 4.A fair dice is rolled once. What is the probability of getting a prime number? (a) 2/3 (b) 1/6 (c) 1/3 (d) 1/2
5. 5.A bag has 8 blue, 3 white and 6 yellow balls. One ball is taken out without looking. What is the probability that it is blue? (a) 9/17 (b) 1/3 (c) 8/9 (d) 8/17
6. 6.Three coins are tossed together. What is the probability of getting exactly one head? (a) 3/8 (b) 1/4 (c) 5/8 (d) 3/5
7. 7.Two coins are tossed together. What is the probability of getting exactly one head? (a) 1/4 (b) 1/2 (c) 1/3 (d) 2/3
8. 8.Two dice are rolled together. What is the probability that the two numbers add up to 6? (a) 1/6 (b) 1/11 (c) 5/36 (d) 5/11
9. 9.A bag has 8 blue, 8 red and 7 green balls. One ball is taken out without looking. What is the probability that it is not blue? (a) 1/3 (b) 8/23 (c) 16/23 (d) 15/23
10. 10.A bag has 4 yellow, 4 red and 3 green balls. One ball is taken out without looking. What is the probability that it is green? (a) 1/3 (b) 3/11 (c) 3/8 (d) 8/11
11. 11.A fair dice is rolled once. What is the probability of getting a multiple of 3? (a) 1/3 (b) 2/3 (c) 1/2 (d) 1/6
12. 12.A bag has 4 blue, 6 red and 7 yellow balls. One ball is taken out without looking. What is the probability that it is not yellow? (a) 7/17 (b) 11/17 (c) 1/3 (d) 10/17
13. 13.A bag has 5 blue, 8 red and 7 yellow balls. One ball is taken out without looking. What is the probability that it is yellow? (a) 13/20 (b) 1/3 (c) 7/20 (d) 7/13
14. 14.A fair dice is rolled once. What is the probability of getting a number less than 3? (a) 2/3 (b) 1/2 (c) 1/6 (d) 1/3
15. 15.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
16. 16.Two dice are rolled together. What is the probability that the two numbers add up to 3? (a) 1/12 (b) 1/11 (c) 1/18 (d) 2/11
17. 17.Two dice are rolled together. What is the probability that the two numbers add up to 7? (a) 7/36 (b) 1/11 (c) 1/6 (d) 6/11
18. 18.A bag has 3 white, 4 green and 2 blue balls. One ball is taken out without looking. What is the probability that it is white? (a) 1/3 (b) 1/2 (c) 4/9 (d) 2/3
19. 19.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
20. 20.Two coins are tossed together. What is the probability of getting at least one head? (a) 1/3 (b) 3/4 (c) 1/4 (d) 1/2
21. 21.A bag has 7 yellow, 7 blue and 6 white balls. One ball is taken out without looking. What is the probability that it is yellow? (a) 1/3 (b) 7/13 (c) 7/20 (d) 13/20
22. 22.Two dice are rolled together. What is the probability that the two numbers add up to 11? (a) 2/11 (b) 1/18 (c) 1/12 (d) 1/11
23. 23.Two dice are rolled together. What is the probability that the two numbers add up to 2? (a) 1/36 (b) 1/18 (c) 1/12 (d) 1/11
24. 24.A bag has 7 white, 5 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) 11/16 (c) 3/4 (d) 5/16
25. 25.A bag has 9 green, 9 red and 7 white balls. One ball is taken out without looking. What is the probability that it is not white? (a) 19/25 (b) 18/25 (c) 7/25 (d) 1/3
26. 26.Two coins are tossed together. What is the probability of getting a head on every coin? (a) 1/2 (b) 3/4 (c) 1/3 (d) 1/4
27. 27.A bag has 9 yellow, 8 red and 2 green balls. One ball is taken out without looking. What is the probability that it is green? (a) 2/17 (b) 2/19 (c) 1/3 (d) 17/19
28. 28.A fair dice is rolled once. What is the probability of getting a number greater than 4? (a) 1/6 (b) 2/3 (c) 1/2 (d) 1/3
29. 29.A fair dice is rolled once. What is the probability of getting a number less than 4? (a) 1/3 (b) 1/6 (c) 2/3 (d) 1/2
30. 30.Two dice are rolled together. What is the probability that the two numbers add up to 4? (a) 1/12 (b) 3/11 (c) 1/9 (d) 1/11
31. 31.A bag has 8 blue, 6 white and 6 yellow balls. One ball is taken out without looking. What is the probability that it is yellow? (a) 1/3 (b) 3/7 (c) 3/10 (d) 7/10
32. 32.Three coins are tossed together. What is the probability of getting at least one head and at least one tail? (a) 3/8 (b) 3/4 (c) 1/8 (d) 1/4
33. 33.A fair dice is rolled once. What is the probability of getting a number less than 5? (a) 5/6 (b) 1/4 (c) 1/3 (d) 2/3
34. 34.A fair dice is rolled once. What is the probability of getting an odd number? (a) 1/3 (b) 1/2 (c) 2/3 (d) 1/6
35. 35.A fair dice is rolled once. What is the probability of getting an even number? (a) 1/6 (b) 1/3 (c) 2/3 (d) 1/2
36. 36.A bag has 7 yellow, 5 green and 4 blue balls. One ball is taken out without looking. What is the probability that it is blue? (a) 3/4 (b) 1/3 (c) 1/4 (d) 5/16
37. 37.A bag has 7 red, 6 white and 5 blue balls. One ball is taken out without looking. What is the probability that it is not white? (a) 1/18 (b) 13/18 (c) 1/3 (d) 2/3
38. 38.A bag has 4 red, 5 yellow and 7 blue balls. One ball is taken out without looking. What is the probability that it is red? (a) 1/3 (b) 3/4 (c) 5/16 (d) 1/4
39. 39.A bag has 2 blue, 2 yellow and 4 red balls. One ball is taken out without looking. What is the probability that it is not blue? (a) 1/3 (b) 7/8 (c) 1/4 (d) 3/4
40. 40.A bag has 3 white, 8 blue and 4 red balls. One ball is taken out without looking. What is the probability that it is not blue? (a) 8/15 (b) 7/15 (c) 1/3 (d) 7/8

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