Probability worksheet — GCSE Foundation

1.The probability that the Hughes family go away during the summer holidays is 3/7. Work out the probability that they do not go away during the summer holidays.

2.At a youth club, 65 members are asked which sports they play. 27 play football, 21 play basketball, and 9 play both. Work out the number of members who play neither sport.

3.An ordinary fair dice is rolled once. Set A is the set of even scores and set B is the set of scores greater than 4. Work out the probability that the score rolled is in set A or in set B or in both.

4.The probability that a plant grown from a seed packet germinates is 7/10. Work out the probability that it does not germinate.

5.The probability that Priya's dentist appointment overruns is 0.35. Work out the probability that it does not overrun.

6.Leo flips a fair coin twice. He makes a list of every possible result of the two flips, writing down what the first flip lands on and then what the second flip lands on. Work out how many of the results in his list contain at least one tail.

7.Spinner C has 3 equal sections, numbered 2, 3 and 5. Spinner D has 6 equal sections, numbered 1 to 6. Both spinners are spun once, and the two numbers are multiplied together. Work out the probability that the product is a multiple of 5.

8.A red fair dice and a blue fair dice are rolled together. Every outcome is listed as an ordered pair, red score then blue score. Work out the probability that the red score is less than the blue score.

9.A fair six-sided dice is rolled 300 times. Work out how many more times you would expect it to land on an even number than on a six.

10.Jack rolls two ordinary fair dice and adds the two scores together. Work out the probability that the total is 6.

11.Two ordinary fair dice are rolled and the two scores are added together. Work out the probability that the total is a prime number.

12.In a trial, a drawing pin was dropped 80 times and landed point-up 52 times. Assuming this relative frequency continues, work out how many times you would expect it to land point-up in 300 drops.

13.A bag contains 5 red counters and 5 green counters. Three counters are taken out one at a time and are not put back. Work out the probability that all three counters are red.

14.A spinner is spun 50 times. It lands on green 18 times. Work out the relative frequency of landing on green.

15.A garden centre recorded 240 plant sales using a frequency tree. The first stage splits the sales into three types: shrubs, bedding plants and trees. 96 sales were shrubs, 114 were bedding plants and the rest were trees. Work out the probability that a sale chosen at random from these 240 was a tree.