Number worksheet — GCSE Foundation

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

2.Work out 18 − 4 × 2

3.Work out an estimate for 113 + 491, by rounding each number to the nearest 100.

4.Write 200 as a product of its prime factors, using index notation.

5.A jug holds 3 1/3 litres of juice. Each glass holds 2/3 of a litre. Work out how many glasses can be filled from the jug.

6.A length, L cm, has the error interval 24.5 ≤ L < 25.5. Write down the degree of accuracy to which the length was measured.

7.In a photo album the ratio of colour photos to black-and-white photos is 9 : 4. Work out the number of black-and-white photos as a fraction of the number of colour photos.

8.A student always writes the digits after the decimal point over a denominator of 100, whatever the number of decimal places. Using this wrong rule, they convert 0.9 to a fraction. Work out the correct fraction that 0.9 is equal to, giving your answer in its simplest form.

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

10.Two lighthouses flash at the start of the same minute. The first lighthouse flashes every 8 minutes and the second flashes every 12 minutes. Work out how many minutes it will be until they next flash together.

11.3/5 of a 5/6 litre bottle of juice is poured out. Work out the exact volume poured out, in litres.

12.Work out the highest common factor of 12 and 18.

13.A shortbread recipe uses flour and butter in the ratio 5 : 2. Yuki changes the recipe by doubling the amount of butter but keeping the amount of flour the same. Work out the fraction of the new mixture that is butter.

14.Write 0.35 as a fraction in its lowest terms.

15.Work out 250 ÷ 1000.