Number worksheet — GCSE Foundation

1.By listing systematically, work out how many two-digit multiples of 5 can be made using the digits 0, 3 and 5, if each digit can be used at most once and the number cannot start with 0.

2.Write 260,000 in standard form.

3.Put these numbers in order, starting with the smallest: 3.2 × 10⁴, 2.9 × 10⁵, 4.1 × 10³

4.A café is planning its lunch menu. It will offer one soup from 3 choices and one sandwich from 4 choices, but the mushroom soup, one of the 3 soups, will only be served with the cheese sandwich, one of the 4 sandwiches, on a normal day. Work out how many different soup-and-sandwich combinations are available on a normal day.

5.The length of a pencil is 8.4 cm, correct to 1 decimal place. Using L for the length of the pencil in centimetres, write down the error interval for L.

6.A number, y, is equal to 8.2 when rounded to 1 decimal place. Write down the error interval for y.

7.Which of these numbers rounds to 0.048 when rounded to 2 significant figures?

8.A plumber charges a call-out fee of £45 and then £28 for each hour she works. She is at a house from 09:15 until 12:45. Work out the total charge.

9.Work out (4 × 10³) × (3 × 10¹). Give your answer in standard form.

10.A red blood cell has a diameter of about 7 × 10⁻⁶ metres. A virus has a diameter about 100 times smaller. Work out the diameter of the virus. Give your answer in standard form.

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

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

13.Sam rounds 0.070268 to 3 significant figures and writes 0.0703. Which of these statements is correct?

14.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.

15.A charity raffle sells 240 tickets at £1.85 each. 40% of the money raised is given to a local hospital. Work out how much money the hospital receives.