← Probability basics lesson New set →

Probability Worksheet for Class 8 Maths Olympiad

Maths Olympiad topic 24: Probability basics · Set 301 · 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 3 red, 2 blue and 6 yellow balls. One ball is taken out without looking. What is the probability that it is red? (a) 1/3 (b) 3/8 (c) 3/11 (d) 8/11
  2. 2.A bag has 9 white, 5 blue and 8 yellow balls. One ball is taken out without looking. What is the probability that it is white? (a) 9/13 (b) 13/22 (c) 9/22 (d) 1/3
  3. 3.A fair dice is rolled once. What is the probability of getting a number greater than 2? (a) 2/3 (b) 5/6 (c) 1/3 (d) 1/4
  4. 4.Three coins are tossed together. What is the probability of getting at least one head and at least one tail? (a) 1/4 (b) 1/8 (c) 3/4 (d) 3/8
  5. 5.Three coins are tossed together. What is the probability of getting exactly one head? (a) 5/8 (b) 1/4 (c) 3/5 (d) 3/8
  6. 6.Three coins are tossed together. What is the probability of getting at least one head? (a) 3/8 (b) 1/8 (c) 7/8 (d) 1/4
  7. 7.Two dice are rolled together. What is the probability that the two numbers add up to 9? (a) 5/36 (b) 4/11 (c) 1/11 (d) 1/9
  8. 8.Two dice are rolled together. What is the probability that the two numbers add up to 2? (a) 1/11 (b) 1/36 (c) 1/18 (d) 1/12
  9. 9.A bag has 6 yellow, 3 white and 2 red balls. One ball is taken out without looking. What is the probability that it is red? (a) 9/11 (b) 1/3 (c) 2/11 (d) 2/9
  10. 10.A fair dice is rolled once. What is the probability of getting an even number? (a) 1/3 (b) 1/6 (c) 2/3 (d) 1/2
  11. 11.Two dice are rolled together. What is the probability that the two numbers add up to 6? (a) 5/36 (b) 1/6 (c) 5/11 (d) 1/11
  12. 12.A bag has 4 white, 8 yellow and 3 blue balls. One ball is taken out without looking. What is the probability that it is yellow? (a) 8/15 (b) 3/5 (c) 1/3 (d) 7/15
  13. 13.A fair dice is rolled once. What is the probability of getting a factor of 6? (a) 1/3 (b) 1/4 (c) 2/3 (d) 5/6
  14. 14.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
  15. 15.A bag has 5 white, 3 green and 9 yellow balls. One ball is taken out without looking. What is the probability that it is not green? (a) 15/17 (b) 3/17 (c) 14/17 (d) 1/3
  16. 16.A bag has 6 white, 3 red and 3 blue balls. One ball is taken out without looking. What is the probability that it is not red? (a) 3/4 (b) 1/3 (c) 1/4 (d) 5/6
  17. 17.Two coins are tossed together. What is the probability of getting a head on every coin? (a) 1/3 (b) 1/4 (c) 1/2 (d) 3/4
  18. 18.A bag has 8 green, 7 blue and 9 yellow balls. One ball is taken out without looking. What is the probability that it is yellow? (a) 1/3 (b) 5/8 (c) 3/8 (d) 3/5
  19. 19.A bag has 2 red, 9 blue and 6 green balls. One ball is taken out without looking. What is the probability that it is not blue? (a) 1/3 (b) 9/17 (c) 8/17 (d) 8/9
  20. 20.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
  21. 21.A bag has 2 green, 4 red and 3 white balls. One ball is taken out without looking. What is the probability that it is green? (a) 2/7 (b) 2/9 (c) 7/9 (d) 1/3
  22. 22.A bag has 7 red, 9 white and 5 yellow balls. One ball is taken out without looking. What is the probability that it is not red? (a) 5/7 (b) 1/21 (c) 1/3 (d) 2/3
  23. 23.A fair dice is rolled once. What is the probability of getting a number greater than 3? (a) 1/6 (b) 2/3 (c) 1/2 (d) 1/3
  24. 24.Two coins are tossed together. What is the probability of getting at least one head? (a) 1/3 (b) 3/4 (c) 1/2 (d) 1/4
  25. 25.A bag has 6 blue, 4 white and 2 yellow balls. One ball is taken out without looking. What is the probability that it is not yellow? (a) 1/6 (b) 1/3 (c) 11/12 (d) 5/6
  26. 26.Three coins are tossed together. What is the probability of getting a head on every coin? (a) 1/4 (b) 1/8 (c) 7/8 (d) 1/7
  27. 27.A bag has 6 blue, 8 white and 3 red balls. One ball is taken out without looking. What is the probability that it is white? (a) 9/17 (b) 8/17 (c) 8/9 (d) 1/3
  28. 28.A bag has 5 white, 8 red and 5 blue balls. One ball is taken out without looking. What is the probability that it is red? (a) 4/9 (b) 4/5 (c) 1/3 (d) 5/9
  29. 29.Two dice are rolled together. What is the probability that the two numbers add up to 10? (a) 1/11 (b) 1/12 (c) 1/9 (d) 3/11
  30. 30.A bag has 7 blue, 6 white and 9 green balls. One ball is taken out without looking. What is the probability that it is blue? (a) 7/15 (b) 1/3 (c) 15/22 (d) 7/22
  31. 31.A bag has 6 blue, 8 red and 8 white balls. One ball is taken out without looking. What is the probability that it is red? (a) 4/7 (b) 7/11 (c) 1/3 (d) 4/11
  32. 32.Two dice are rolled together. What is the probability that the two numbers add up to 4? (a) 1/12 (b) 3/11 (c) 1/11 (d) 1/9
  33. 33.A bag has 4 yellow, 9 red and 4 blue balls. One ball is taken out without looking. What is the probability that it is not red? (a) 8/9 (b) 9/17 (c) 8/17 (d) 1/3
  34. 34.A fair dice is rolled once. What is the probability of getting a number less than 5? (a) 5/6 (b) 1/4 (c) 1/3 (d) 2/3
  35. 35.A bag has 6 blue, 7 red and 5 green balls. One ball is taken out without looking. What is the probability that it is green? (a) 1/3 (b) 5/18 (c) 13/18 (d) 5/13
  36. 36.A fair dice is rolled once. What is the probability of getting a number less than 4? (a) 1/2 (b) 2/3 (c) 1/3 (d) 1/6
  37. 37.A bag has 5 yellow, 9 red and 6 white balls. One ball is taken out without looking. What is the probability that it is white? (a) 3/7 (b) 1/3 (c) 7/10 (d) 3/10
  38. 38.A fair dice is rolled once. What is the probability of getting a number less than 3? (a) 2/3 (b) 1/2 (c) 1/6 (d) 1/3
  39. 39.Two dice are rolled together. What is the probability that the two numbers add up to 11? (a) 2/11 (b) 1/12 (c) 1/11 (d) 1/18
  40. 40.A fair dice is rolled once. What is the probability of getting a prime number? (a) 2/3 (b) 1/2 (c) 1/3 (d) 1/6

Answer key

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

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