Probability Worksheet for Class 8 Maths Olympiad

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

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