Probability Worksheet for Class 8 Maths Olympiad

Maths Olympiad topic 24: Probability basics · Set 423 · 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.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
2. 2.Two dice are rolled together. What is the probability that the two numbers add up to 4? (a) 1/9 (b) 3/11 (c) 1/12 (d) 1/11
3. 3.Three coins are tossed together. What is the probability of getting exactly one head? (a) 3/8 (b) 5/8 (c) 1/4 (d) 3/5
4. 4.A bag has 6 white, 4 blue and 2 red balls. One ball is taken out without looking. What is the probability that it is not red? (a) 1/6 (b) 11/12 (c) 1/3 (d) 5/6
5. 5.Two coins are tossed together. What is the probability of getting exactly one head? (a) 1/3 (b) 1/2 (c) 1/4 (d) 2/3
6. 6.Two coins are tossed together. What is the probability of getting at least one head and at least one tail? (a) 1/3 (b) 2/3 (c) 1/2 (d) 1/4
7. 7.Two dice are rolled together. What is the probability that the two numbers add up to 5? (a) 1/11 (b) 5/36 (c) 4/11 (d) 1/9
8. 8.A bag has 7 blue, 7 green and 4 yellow balls. One ball is taken out without looking. What is the probability that it is yellow? (a) 2/9 (b) 2/7 (c) 1/3 (d) 7/9
9. 9.Two dice are rolled together. What is the probability that the two numbers add up to 3? (a) 2/11 (b) 1/18 (c) 1/12 (d) 1/11
10. 10.Two dice are rolled together. What is the probability that the two numbers add up to 9? (a) 1/9 (b) 5/36 (c) 1/11 (d) 4/11
11. 11.A bag has 8 white, 7 red and 4 blue balls. One ball is taken out without looking. What is the probability that it is blue? (a) 4/15 (b) 1/3 (c) 15/19 (d) 4/19
12. 12.A bag has 2 green, 6 yellow and 2 red balls. One ball is taken out without looking. What is the probability that it is not green? (a) 1/5 (b) 4/5 (c) 1/3 (d) 9/10
13. 13.A fair dice is rolled once. What is the probability of getting an even number? (a) 1/3 (b) 2/3 (c) 1/6 (d) 1/2
14. 14.A bag has 3 red, 9 green and 5 yellow 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
15. 15.Three coins are tossed together. What is the probability of getting a head on every coin? (a) 1/7 (b) 7/8 (c) 1/4 (d) 1/8
16. 16.A fair dice is rolled once. What is the probability of getting a multiple of 3? (a) 1/3 (b) 1/6 (c) 2/3 (d) 1/2
17. 17.A fair dice is rolled once. What is the probability of getting a number greater than 1? (a) 1/5 (b) 1/6 (c) 5/6 (d) 1/3
18. 18.A bag has 3 green, 9 red and 7 blue balls. One ball is taken out without looking. What is the probability that it is not red? (a) 10/19 (b) 11/19 (c) 9/19 (d) 1/3
19. 19.A bag has 6 yellow, 4 white and 2 red balls. One ball is taken out without looking. What is the probability that it is not white? (a) 3/4 (b) 1/3 (c) 2/3 (d) 1/12
20. 20.Two dice are rolled together. What is the probability that the two numbers add up to 12? (a) 1/11 (b) 1/12 (c) 1/18 (d) 1/36
21. 21.A fair dice is rolled once. What is the probability of getting a prime number? (a) 2/3 (b) 1/6 (c) 1/2 (d) 1/3
22. 22.A bag has 5 blue, 9 yellow and 8 red balls. One ball is taken out without looking. What is the probability that it is not blue? (a) 5/22 (b) 1/3 (c) 17/22 (d) 9/11
23. 23.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
24. 24.A bag has 6 yellow, 6 red and 5 white balls. One ball is taken out without looking. What is the probability that it is not red? (a) 6/17 (b) 1/3 (c) 11/17 (d) 12/17
25. 25.A fair dice is rolled once. What is the probability of getting a factor of 6? (a) 2/3 (b) 5/6 (c) 1/3 (d) 1/4
26. 26.Two dice are rolled together. What is the probability that the two numbers add up to 8? (a) 1/11 (b) 5/11 (c) 5/36 (d) 1/6
27. 27.Two dice are rolled together. What is the probability that the two numbers add up to 10? (a) 1/11 (b) 1/9 (c) 1/12 (d) 3/11
28. 28.A fair dice is rolled once. What is the probability of getting an odd number? (a) 1/2 (b) 2/3 (c) 1/3 (d) 1/6
29. 29.A bag has 6 red, 5 yellow and 8 green balls. One ball is taken out without looking. What is the probability that it is not green? (a) 12/19 (b) 1/3 (c) 8/19 (d) 11/19
30. 30.Two dice are rolled together. What is the probability that the two numbers add up to 6? (a) 1/6 (b) 5/11 (c) 1/11 (d) 5/36
31. 31.A bag has 4 red, 5 green and 2 blue balls. One ball is taken out without looking. What is the probability that it is not green? (a) 7/11 (b) 1/3 (c) 6/11 (d) 5/11
32. 32.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
33. 33.A fair dice is rolled once. What is the probability of getting a number less than 5? (a) 1/4 (b) 2/3 (c) 1/3 (d) 5/6
34. 34.A bag has 7 green, 2 white and 7 red balls. One ball is taken out without looking. What is the probability that it is not white? (a) 1/8 (b) 1/3 (c) 15/16 (d) 7/8
35. 35.Two dice are rolled together. What is the probability that the two numbers add up to 2? (a) 1/11 (b) 1/18 (c) 1/36 (d) 1/12
36. 36.A bag has 4 blue, 9 green and 3 red balls. One ball is taken out without looking. What is the probability that it is red? (a) 1/3 (b) 3/13 (c) 13/16 (d) 3/16
37. 37.A bag has 7 white, 3 blue and 5 red balls. One ball is taken out without looking. What is the probability that it is white? (a) 8/15 (b) 7/8 (c) 1/3 (d) 7/15
38. 38.A fair dice is rolled once. What is the probability of getting a number less than 2? (a) 1/5 (b) 5/6 (c) 1/6 (d) 1/3
39. 39.Three coins are tossed together. What is the probability of getting at least one head? (a) 7/8 (b) 3/8 (c) 1/8 (d) 1/4
40. 40.A bag has 9 white, 6 yellow and 4 green balls. One ball is taken out without looking. What is the probability that it is not yellow? (a) 14/19 (b) 13/19 (c) 1/3 (d) 6/19

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