Number worksheet — GCSE Foundation

1.The mass of a radioactive sample, in grams, n years after it was first weighed is modelled by M = 200 × (1/2)ⁿ. Work out the mass the model gives after 3 years.

2.Which of these numbers is the largest: −9, −7, −4, −2?

3.A recipe uses 0.625 kg of flour. Write this mass as a fraction of a kilogram, in its simplest form.

4.For any two whole numbers, the product of the numbers is equal to the product of their highest common factor and their lowest common multiple. The highest common factor of 6 and 8 is 2, and 6 × 8 = 48. Work out the lowest common multiple of 6 and 8.

5.Work out the lowest common multiple of 4 and 6.

6.A company sells 4 × 10³ items per day, each priced at £2.50. It operates for 3 × 10² days a year. Work out the company's total revenue for the year. Give your answer in standard form.

7.A concert hall has 300 seats. 20% of the seats are in the balcony. Work out how many of the seats are in the balcony.

8.The thickness of a sheet of card is 0.02384 cm. Write this thickness correct to 2 significant figures.

9.Hannah works out 3.1 × 19.6 on her calculator and writes down 6.076. Work out an estimate for 3.1 × 19.6, by rounding each number to 1 significant figure.

10.Work out −4.5 + 2.8.

11.In a box of chocolates 5/8 are milk chocolates and the rest are dark chocolates. Work out the number of dark chocolates as a fraction of the number of milk chocolates.

12.Put these three numbers in order of size, starting with the smallest: 3/8, 0.4, 0.35

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

14.A tin of soup has a mass of 450 g. A bag of potatoes has a mass of 2.6 kg. Work out the total mass, in kilograms.

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