Number worksheet — GCSE Foundation

1.The number 24 can be written as 2³ × 3, and the number 60 can be written as 2² × 3 × 5. Work out the lowest common multiple of 24 and 60.

2.Priya has 24 red beads and 36 blue beads. She makes identical bracelets, using every bead and with none left over. Work out the greatest number of bracelets she can make.

3.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.

4.A rectangular patio measures 90 cm by 120 cm. Ben wants to cover it exactly with identical square tiles, as large as possible, with no tiles cut. Work out the side length of the largest square tile he can use.

5.A necklace is made from red beads and gold beads in the ratio 7 : 3. What fraction of the beads are gold?

6.Work out 2 × 3 × 5 + 1 and decide whether the result is a prime number.

7.Write 90 as a product of its prime factors.

8.Work out an estimate for 588 ÷ 31, by rounding each number to 1 significant figure.

9.A garden has flowers, herbs and vegetables in the ratio 2 : 3 : 4. What fraction of the garden is not vegetables?

10.A circle has a radius of 3 cm. Which of these is the exact area of the circle?

11.Jack buys 3 books, each costing £4.25, and pays with a £20 note. Work out how much change he receives.

12.Work out 1 1/2 ÷ 3/4 exactly, giving your answer in its simplest form.

13.A machine fills bags of sugar and shows the mass of each bag to the nearest 10 g. A checker rejects any bag whose actual mass is less than 996 g. One bag shows a mass of 1,000 g on the machine. Decide whether this bag could be rejected, and give a reason for your answer.

14.Work out 35% of 180.

15.A space probe is 7.5 × 10⁸ km from Earth. Write this distance as an ordinary number.