Relative frequency and the probability scale worksheet — GCSE Foundation

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

2.The probability that a pupil chosen at random has a nut allergy is 1/10. There are 30 pupils in a class. Work out how many of the 30 pupils would be expected to have a nut allergy.

3.The probability that Amelia's bus is late on a school morning is 9/10. Write this probability as a percentage.

4.A fair six-sided dice is rolled once. Write down the probability that the score is an even number.

5.Two goalkeepers face penalty kicks. Elin saves 34% of the penalties she faces. Noah saves 11/32 of the penalties he faces. Which statement correctly compares them?

6.A fair six-sided dice is rolled once. Work out the probability that the score is greater than 4.

7.A fair six-sided dice is rolled once. Write down the probability of rolling a 6.

8.A survey found that, of 250 shoppers questioned, 68% said they had used a self-checkout in the past month. A different store expects 1400 shoppers this week. Using this relative frequency, work out how many of the 1400 shoppers would be expected to have used a self-checkout in the past month.

9.A market research company found that, out of 120 shoppers surveyed, 42 preferred paper bags to plastic bags. A supermarket expects 900 shoppers this week. Using this relative frequency, work out how many of the 900 shoppers would be expected to prefer paper bags.

10.A machine produces bolts. In a sample of 250 bolts, 15 are faulty. Work out the relative frequency of a bolt being faulty, giving your answer as a fraction in its simplest form.

11.The probability that a spinner lands on blue is 2/5. Write this probability as a percentage.

12.A spinner is divided into 8 equal sections. 3 of the sections are red and the rest are not red. The spinner is spun once. Work out the probability that it does not land on red.

13.A bag is known to contain red, blue and green counters in equal numbers, so the theoretical probability of taking each colour is 1/3. In 90 trials with replacement, red was taken 38 times, blue was taken 26 times and green was taken 26 times. Which colour is over-represented compared with its theoretical probability?

14.An ordinary pack of 52 playing cards contains 13 hearts. One card is taken at random from the pack. Work out the probability that the card is not a heart. Give your answer as a percentage.

15.On the probability scale from 0 to 1, which word best describes an event with probability 0.9?