Number worksheet — GCSE Foundation

1.Work out (8 × 10⁻⁵) × (5 × 10³). Give your answer in standard form.

2.The error interval for the mass of a suitcase, m kg, is given as 22.5 ≤ m < 23.5. Write down the mass of the suitcase, correct to the nearest whole number.

3.After a price increase of 10%, a laptop costs £330. Work out the original price.

4.A flight departs at 21:35 and lands at 06:10 the following morning. Work out the total flight time.

5.A photography studio offers 4 backdrops and 3 outfits for a portrait session. The plain grey backdrop, one of the 4 backdrops, cannot be used with the formal suit outfit, one of the 3 outfits. Work out how many different backdrop-and-outfit combinations are possible.

6.Light travels at 3 × 10⁸ metres per second. Work out how far light travels in 2 × 10⁻⁶ seconds. Give your answer in standard form.

7.A recipe uses 160 g of flour. Sam wants to increase the amount by 1/4. Work out the new amount of flour.

8.Josh buys 7 pencils at 85p each. He pays with a £10 note. Work out his change.

9.A café offers 3 types of soup and 4 types of bread roll. Work out how many different combinations of one soup and one bread roll are possible.

10.2/3 of an amount of money is £30. Work out the amount.

11.Petrol costs £1.48 per litre. Sam buys 35 litres and pays with three £20 notes. Work out his change.

12.To estimate the cost of buying 38.7 m of rope at £21.40 per metre, both numbers are first rounded to 1 significant figure. Work out the estimate.

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

14.A washing machine costs £320 before VAT. VAT is charged at 20%. Work out the total price including VAT.

15.The rainfall in a town during April is recorded as 62.4 mm, correct to 1 decimal place. Write down the error interval for the actual rainfall, r mm.