Number worksheet — GCSE Foundation

1.Ava measures a metal rod and records its length as 15 cm, correct to the nearest centimetre. Ben measures the same rod and records its length as 14.8 cm, correct to the nearest 0.1 cm. Decide whether both records can be correct, and give a reason for your answer.

2.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.

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

4.Which of these numbers rounds to 0.048 when rounded to 2 significant figures?

5.Work out (8 × 10⁻⁵) × (5 × 10³). Give your answer in standard form.

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.

7.3.4 × 10⁵ is written as an ordinary number. Work out this number.

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

9.A jumper is reduced by 15% in a sale to a price of £42.50. Work out the original price.

10.A speed camera measures a car's speed as 34 mph, correct to the nearest mph. Work out the smallest possible actual speed of the car, in mph.

11.A cake recipe needs 3/4 of a kilogram of sugar. Aisha wants to make half the recipe. Work out how much sugar she needs, giving your answer as a fraction of a kilogram in its simplest form.

12.Two fair six-sided dice are rolled together. One die is red and the other is blue. Work out how many different outcomes are possible.

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.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.

15.A quiz has 50 questions. Freya answers 10% of them incorrectly. Work out how many questions she answers incorrectly.