Number worksheet — GCSE Foundation

1.Priya adds 3.6 and 0.45 on paper and writes down 3.65 as her answer. Work out the correct value of 3.6 + 0.45.

2.Work out an estimate for 397 ÷ 21, by rounding each number to 1 significant figure.

3.A student works out the exact area of a circle with radius 4 cm by squaring the radius but forgetting to multiply by π. Work out the correct exact area of the circle, in terms of π.

4.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.

5.The population of a planet is 8 × 10⁹. Write this population as an ordinary number.

6.Work out −6 × (−3).

7.Write these numbers in order, starting with the largest: 7/8, 0.8, 78%, 17/20

8.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.

9.Work out an estimate for 6.4 × 3.9, by rounding each number to the nearest whole number.

10.Find the missing number: 17 × ▢ = 391

11.Work out 3 + 4 × 2²

12.Which of these units would be most appropriate to use when stating the mass of a small car?

13.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.

15.A charity raises money from a raffle and a cake sale in the ratio 5 : 3. Altogether the charity raises £320. Work out how much money the cake sale raised.