← Probability basics lesson New set →

Probability Worksheet for Class 8 Maths Olympiad

Maths Olympiad topic 24: Probability basics · Set 129 · 40 questions
TalentJR

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.

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

Answer key

  1. 3/5
  2. 1/2
  3. 3/8
  4. 2/13
  5. 3/8
  6. 1/18
  7. 15/17
  8. 3/4
  9. 1/2
  10. 1/6
  11. 1/8
  12. 7/15
  13. 1/12
  14. 1/2
  15. 1/18
  16. 4/15
  17. 5/36
  18. 7/17
  19. 6/23
  20. 12/17
  21. 1/36
  22. 1/2
  23. 4/7
  24. 9/14
  25. 1/3
  26. 5/36
  27. 1/6
  28. 3/8
  29. 1/3
  30. 14/17
  31. 1/2
  32. 1/9
  33. 2/3
  34. 3/4
  35. 5/16
  36. 1/2
  37. 1/9
  38. 1/9
  39. 1/12
  40. 3/14

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