Number worksheet — GCSE Foundation

1.A spreadsheet shows that 812 − 397 = 315. Work out an estimate for 812 − 397, by rounding each number to the nearest 100, to check whether the spreadsheet's answer is reasonable.

2.Work out √49

3.Leah measures the length of her classroom with a tape measure marked in centimetres. She writes the length down as 7.3157 m. Give a reason why this is not an appropriate degree of accuracy.

4.In a science experiment, the temperature of a liquid is recorded as 18.6 °C, correct to the nearest 0.2 °C. Write down the error interval for the actual temperature, T °C.

5.A metal cube has a mass of 540 g and a volume of 60 cm³. Work out its density in g/cm³.

6.Write 0.005 in standard form.

7.A number, n, is equal to 3.7 when rounded to 1 decimal place. Write down the error interval for n.

8.Is 120 divisible by 5? Give a reason for your answer.

9.Work out −7 − (−3).

10.The distance from the Earth to the Moon is 384,000 km. Write this distance in standard form, in kilometres.

11.Round 592.5 to the nearest 10.

12.Oliver drives 95 km at an average speed of 50 km/h. Work out an estimate for the time the journey takes, by rounding the distance to the nearest 100 km.

13.A café offers 3 types of soup and 4 types of bread roll. Work out how many different combinations of one soup and one bread roll are possible.

14.A cinema has 21 rows of seats with 29 seats in each row. Work out an estimate for the number of people the cinema can hold, by rounding each number to 1 significant figure.

15.Two allotments are combined. Allotment A grows vegetables and flowers in the ratio 3 : 2, and has 20 plots in total. Allotment B grows vegetables and flowers in the ratio 1 : 4, and has 20 plots in total. Work out the fraction of all the plots, in both allotments combined, that grow vegetables.