Probability Worksheet for Class 8 Maths Olympiad

Maths Olympiad topic 24: Probability basics · Set 435 · 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) 1/9 (b) 4/11 (c) 1/11 (d) 5/36
2. 2.A fair dice is rolled once. What is the probability of getting a number less than 3? (a) 1/6 (b) 2/3 (c) 1/2 (d) 1/3
3. 3.A bag has 7 yellow, 8 white and 6 red balls. One ball is taken out without looking. What is the probability that it is yellow? (a) 1/2 (b) 1/3 (c) 8/21 (d) 2/3
4. 4.A fair dice is rolled once. What is the probability of getting a factor of 6? (a) 5/6 (b) 2/3 (c) 1/4 (d) 1/3
5. 5.Two coins are tossed together. What is the probability of getting at least one head? (a) 1/4 (b) 1/3 (c) 1/2 (d) 3/4
6. 6.A fair dice is rolled once. What is the probability of getting an even number? (a) 2/3 (b) 1/3 (c) 1/6 (d) 1/2
7. 7.Two dice are rolled together. What is the probability that the two numbers add up to 6? (a) 5/11 (b) 5/36 (c) 1/6 (d) 1/11
8. 8.Three coins are tossed together. What is the probability of getting a head on every coin? (a) 1/4 (b) 7/8 (c) 1/7 (d) 1/8
9. 9.A bag has 7 yellow, 2 red and 3 blue balls. One ball is taken out without looking. What is the probability that it is red? (a) 1/5 (b) 5/6 (c) 1/3 (d) 1/6
10. 10.A fair dice is rolled once. What is the probability of getting a multiple of 3? (a) 1/6 (b) 2/3 (c) 1/2 (d) 1/3
11. 11.Two dice are rolled together. What is the probability that the two numbers add up to 5? (a) 1/9 (b) 1/11 (c) 4/11 (d) 5/36
12. 12.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
13. 13.A bag has 2 blue, 7 red and 7 white balls. One ball is taken out without looking. What is the probability that it is red? (a) 9/16 (b) 7/9 (c) 7/16 (d) 1/3
14. 14.A bag has 2 white, 3 green and 4 red balls. One ball is taken out without looking. What is the probability that it is red? (a) 5/9 (b) 1/3 (c) 4/5 (d) 4/9
15. 15.A bag has 2 green, 7 white and 8 yellow balls. One ball is taken out without looking. What is the probability that it is green? (a) 15/17 (b) 1/3 (c) 2/17 (d) 2/15
16. 16.A bag has 5 red, 6 green and 8 blue balls. One ball is taken out without looking. What is the probability that it is not green? (a) 6/19 (b) 13/19 (c) 14/19 (d) 1/3
17. 17.A fair dice is rolled once. What is the probability of getting an odd number? (a) 1/2 (b) 2/3 (c) 1/6 (d) 1/3
18. 18.Two dice are rolled together. What is the probability that the two numbers add up to 4? (a) 1/9 (b) 1/12 (c) 1/11 (d) 3/11
19. 19.Three coins are tossed together. What is the probability of getting exactly one head? (a) 3/8 (b) 1/4 (c) 3/5 (d) 5/8
20. 20.A bag has 5 white, 7 red and 2 yellow balls. One ball is taken out without looking. What is the probability that it is not yellow? (a) 13/14 (b) 1/7 (c) 6/7 (d) 1/3
21. 21.A bag has 3 white, 8 yellow and 6 green balls. One ball is taken out without looking. What is the probability that it is not green? (a) 11/17 (b) 1/3 (c) 12/17 (d) 6/17
22. 22.A bag has 9 white, 8 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) 2/5 (c) 13/20 (d) 3/5
23. 23.Two coins are tossed together. What is the probability of getting at least one head and at least one tail? (a) 1/4 (b) 2/3 (c) 1/3 (d) 1/2
24. 24.A bag has 7 white, 3 blue and 8 green balls. One ball is taken out without looking. What is the probability that it is white? (a) 11/18 (b) 1/3 (c) 7/11 (d) 7/18
25. 25.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
26. 26.Two coins are tossed together. What is the probability of getting exactly one head? (a) 2/3 (b) 1/2 (c) 1/3 (d) 1/4
27. 27.A bag has 3 green, 7 blue and 5 white balls. One ball is taken out without looking. What is the probability that it is green? (a) 1/4 (b) 1/3 (c) 4/5 (d) 1/5
28. 28.A bag has 6 green, 6 white and 8 red balls. One ball is taken out without looking. What is the probability that it is green? (a) 3/7 (b) 7/10 (c) 1/3 (d) 3/10
29. 29.A fair dice is rolled once. What is the probability of getting a number less than 5? (a) 1/3 (b) 1/4 (c) 2/3 (d) 5/6
30. 30.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
31. 31.A bag has 2 yellow, 2 red and 6 white balls. One ball is taken out without looking. What is the probability that it is white? (a) 3/5 (b) 2/5 (c) 7/10 (d) 1/3
32. 32.A bag has 6 red, 6 yellow and 3 green balls. One ball is taken out without looking. What is the probability that it is yellow? (a) 1/3 (b) 2/3 (c) 3/5 (d) 2/5
33. 33.A bag has 6 yellow, 2 green and 8 red balls. One ball is taken out without looking. What is the probability that it is not red? (a) 1/3 (b) 1/16 (c) 1/2 (d) 9/16
34. 34.A fair dice is rolled once. What is the probability of getting a prime number? (a) 2/3 (b) 1/3 (c) 1/2 (d) 1/6
35. 35.A bag has 2 green, 7 white and 7 yellow balls. One ball is taken out without looking. What is the probability that it is not green? (a) 1/8 (b) 1/3 (c) 15/16 (d) 7/8
36. 36.A bag has 3 green, 3 yellow and 4 red balls. One ball is taken out without looking. What is the probability that it is green? (a) 3/10 (b) 3/7 (c) 7/10 (d) 1/3
37. 37.A bag has 5 white, 3 yellow and 9 blue balls. One ball is taken out without looking. What is the probability that it is yellow? (a) 3/17 (b) 1/3 (c) 14/17 (d) 3/14
38. 38.Three coins are tossed together. What is the probability of getting at least one head? (a) 3/8 (b) 1/8 (c) 1/4 (d) 7/8
39. 39.A bag has 6 white, 7 red and 9 blue balls. One ball is taken out without looking. What is the probability that it is red? (a) 1/3 (b) 7/22 (c) 15/22 (d) 7/15
40. 40.A bag has 7 green, 2 yellow and 3 red balls. One ball is taken out without looking. What is the probability that it is yellow? (a) 1/3 (b) 5/6 (c) 1/6 (d) 1/5

Free maths olympiad lessons, practice and worksheets at talentjr.in/maths-olympiad