Number worksheet — GCSE Foundation

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

2.The number 72 can be written as 2³ × 3², and the number 108 can be written as 2² × 3³. Work out the highest common factor of 72 and 108.

3.A tin of beans has a mass of 650 g. A bag of rice has a mass of 1.35 kg. Work out the total mass, in kilograms.

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

5.The thickness of a sheet of card is 0.02384 cm. Write this thickness correct to 2 significant figures.

6.A train leaves Leeds at 14:35. The journey takes 1 hour 50 minutes. Work out the time the train arrives. Give your answer using the 24-hour clock.

7.A bag holds 50 counters. 2/5 of them are red and the rest are blue. 5 red counters are then taken out of the bag. Work out the new ratio of red counters to blue counters. Give your answer in its simplest form.

8.Write these numbers in order, starting with the smallest: −1.4, 5/4, −6/5, 1.3, 0

9.Simplify 2³ × 2⁴, giving your answer as a single power of 2.

10.A measuring jug shows a volume of 340 ml, correct to the nearest 20 ml. Work out the smallest possible volume in the jug.

11.For any two whole numbers, the product of the numbers is equal to the product of their highest common factor and their lowest common multiple. The highest common factor of 6 and 8 is 2, and 6 × 8 = 48. Work out the lowest common multiple of 6 and 8.

12.Work out 36 ÷ (2 × 3)

13.A box holds 140 pens. 25% of the pens are red. Work out how many of the pens are red.

14.Work out (−6) + (−4) × 3

15.Write 60 as a product of its prime factors, using index notation.