Probability Worksheet for Class 8 Maths Olympiad

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

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