Number worksheet — GCSE Foundation

1.A cheetah runs at a steady speed of 25 metres per second. Work out this speed in kilometres per hour.

2.Work out an estimate for 8,900 ÷ 29, by rounding each number to 1 significant figure.

3.The diameter of an artificial silk fibre is 4 × 10⁻⁶ metres. One nanometre is 10⁻⁹ metres. Work out the diameter of the fibre in nanometres.

4.A florist has 5 different flowers. Freya picks 3 of them to make a small bunch, and the order in which she picks them does not matter. Work out how many different bunches she could make.

5.A recipe needs 0.485 kg of flour per cake. A bakery estimates its flour order by rounding this amount to 1 significant figure, then multiplying by the 60 cakes it plans to bake. Work out the bakery's estimate for the total flour needed, in kg.

6.A supermarket sells apples at £1.85 per kg. Anna buys 3.6 kg of apples. Estimate the cost by rounding each number to 1 significant figure before multiplying. Work out Anna's estimate.

7.A jumper is reduced by 15% in a sale to a price of £42.50. Work out the original price.

8.Work out 1 − 1/2 − 1/4 − 1/8 − 1/16. Give your answer as a fraction.

9.The number 36 can be written as 2² × 3², and the number 84 can be written as 2² × 3 × 7. Work out the highest common factor of 36 and 84.

10.A semicircle has a diameter of 8 cm. Work out the exact area of the semicircle, in terms of π.

11.Work out 3/4 − 5/12 exactly, giving your answer in its simplest form.

12.Work out an estimate for 89 + 52, by rounding each number to the nearest 10.

13.Write 45,000 in standard form.

14.A spreadsheet shows that 812 − 397 = 315. Work out an estimate for 812 − 397, by rounding each number to the nearest 100, to check whether the spreadsheet's answer is reasonable.

15.£60 is shared between Amir, Bo and Chen in the ratio 1:2:3. Work out the fraction of the £60 that Amir and Bo receive together.