Probability Worksheet for Class 8 Maths Olympiad

Maths Olympiad topic 24: Probability basics · Set 178 · 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 7? (a) 1/6 (b) 1/11 (c) 6/11 (d) 7/36
2. 2.A fair dice is rolled once. What is the probability of getting a multiple of 3? (a) 1/6 (b) 1/3 (c) 1/2 (d) 2/3
3. 3.A fair dice is rolled once. What is the probability of getting a number greater than 1? (a) 1/3 (b) 1/6 (c) 1/5 (d) 5/6
4. 4.A fair dice is rolled once. What is the probability of getting a number less than 2? (a) 1/3 (b) 1/6 (c) 1/5 (d) 5/6
5. 5.Two dice are rolled together. What is the probability that the two numbers add up to 3? (a) 1/12 (b) 2/11 (c) 1/11 (d) 1/18
6. 6.A bag has 2 red, 3 green and 7 yellow balls. One ball is taken out without looking. What is the probability that it is not yellow? (a) 7/12 (b) 5/12 (c) 5/7 (d) 1/3
7. 7.Two dice are rolled together. What is the probability that the two numbers add up to 2? (a) 1/36 (b) 1/11 (c) 1/12 (d) 1/18
8. 8.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
9. 9.A bag has 2 white, 6 green and 9 blue balls. One ball is taken out without looking. What is the probability that it is not green? (a) 11/17 (b) 12/17 (c) 6/17 (d) 1/3
10. 10.Two dice are rolled together. What is the probability that the two numbers add up to 11? (a) 1/18 (b) 2/11 (c) 1/11 (d) 1/12
11. 11.Three coins are tossed together. What is the probability of getting exactly one head? (a) 5/8 (b) 1/4 (c) 3/8 (d) 3/5
12. 12.A bag has 5 green, 5 yellow and 4 blue balls. One ball is taken out without looking. What is the probability that it is yellow? (a) 5/14 (b) 9/14 (c) 5/9 (d) 1/3
13. 13.Two dice are rolled together. What is the probability that the two numbers add up to 4? (a) 1/12 (b) 1/9 (c) 1/11 (d) 3/11
14. 14.Three coins are tossed together. What is the probability of getting at least one head? (a) 3/8 (b) 7/8 (c) 1/4 (d) 1/8
15. 15.A bag has 9 red, 6 green and 2 yellow balls. One ball is taken out without looking. What is the probability that it is red? (a) 1/3 (b) 10/17 (c) 9/17 (d) 8/17
16. 16.A fair dice is rolled once. What is the probability of getting a factor of 6? (a) 5/6 (b) 1/3 (c) 2/3 (d) 1/4
17. 17.A bag has 7 yellow, 6 blue and 4 green balls. One ball is taken out without looking. What is the probability that it is not yellow? (a) 11/17 (b) 7/17 (c) 10/17 (d) 1/3
18. 18.A bag has 2 white, 3 red and 7 yellow balls. One ball is taken out without looking. What is the probability that it is not white? (a) 1/3 (b) 11/12 (c) 1/6 (d) 5/6
19. 19.Two coins are tossed together. What is the probability of getting exactly one head? (a) 1/3 (b) 1/4 (c) 1/2 (d) 2/3
20. 20.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
21. 21.Two coins are tossed together. What is the probability of getting a head on every coin? (a) 1/2 (b) 1/3 (c) 1/4 (d) 3/4
22. 22.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
23. 23.A bag has 2 blue, 5 red and 6 yellow balls. One ball is taken out without looking. What is the probability that it is yellow? (a) 6/13 (b) 1/3 (c) 6/7 (d) 7/13
24. 24.Two coins are tossed together. What is the probability of getting at least one head and at least one tail? (a) 1/3 (b) 1/2 (c) 2/3 (d) 1/4
25. 25.A bag has 4 yellow, 3 blue and 3 white balls. One ball is taken out without looking. What is the probability that it is not yellow? (a) 2/5 (b) 7/10 (c) 3/5 (d) 1/3
26. 26.Three coins are tossed together. What is the probability of getting a head on every coin? (a) 1/8 (b) 7/8 (c) 1/7 (d) 1/4
27. 27.A fair dice is rolled once. What is the probability of getting an even number? (a) 1/6 (b) 1/2 (c) 1/3 (d) 2/3
28. 28.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
29. 29.A fair dice is rolled once. What is the probability of getting an odd number? (a) 1/6 (b) 2/3 (c) 1/2 (d) 1/3
30. 30.A bag has 7 green, 9 red and 7 blue balls. One ball is taken out without looking. What is the probability that it is not red? (a) 14/23 (b) 15/23 (c) 1/3 (d) 9/23
31. 31.A bag has 8 blue, 2 green and 6 red balls. One ball is taken out without looking. What is the probability that it is green? (a) 1/3 (b) 7/8 (c) 1/7 (d) 1/8
32. 32.A bag has 6 yellow, 6 green and 3 white balls. One ball is taken out without looking. What is the probability that it is not green? (a) 1/3 (b) 2/5 (c) 2/3 (d) 3/5
33. 33.Two dice are rolled together. What is the probability that the two numbers add up to 10? (a) 1/11 (b) 3/11 (c) 1/9 (d) 1/12
34. 34.A bag has 2 white, 3 green and 9 yellow balls. One ball is taken out without looking. What is the probability that it is not green? (a) 1/3 (b) 11/14 (c) 3/14 (d) 6/7
35. 35.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
36. 36.A bag has 4 white, 2 yellow and 7 red balls. One ball is taken out without looking. What is the probability that it is red? (a) 6/13 (b) 1/3 (c) 8/13 (d) 7/13
37. 37.A bag has 9 red, 5 yellow and 6 white balls. One ball is taken out without looking. What is the probability that it is not yellow? (a) 4/5 (b) 1/4 (c) 1/3 (d) 3/4
38. 38.A bag has 3 red, 3 green and 2 white balls. One ball is taken out without looking. What is the probability that it is green? (a) 3/5 (b) 5/8 (c) 3/8 (d) 1/3
39. 39.A fair dice is rolled once. What is the probability of getting a number less than 5? (a) 2/3 (b) 5/6 (c) 1/3 (d) 1/4
40. 40.A fair dice is rolled once. What is the probability of getting a number greater than 3? (a) 1/2 (b) 1/6 (c) 1/3 (d) 2/3

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