Number worksheet — GCSE Foundation

1.Which of these is written correctly in standard form?

2.A jacket normally costs £65. In a sale it is reduced by 20%, and the shop then takes a further £5 off at the till. Work out the final price.

3.A recipe states that a cake needs 200 g of flour, correct to the nearest 25 g. Work out the smallest possible mass of flour, in grams, that could actually be used.

4.By listing systematically, work out how many two-digit multiples of 5 can be made using the digits 0, 3 and 5, if each digit can be used at most once and the number cannot start with 0.

5.Write these three numbers in order, starting with the smallest: 3/5, 0.55, 58%

6.3.4 × 10⁵ is written as an ordinary number. Work out this number.

7.Round 6.283 to 1 significant figure.

8.A red blood cell has a diameter of about 7 × 10⁻⁶ metres. A virus has a diameter about 100 times smaller. Work out the diameter of the virus. Give your answer in standard form.

9.A block of butter has a mass of 250 g, correct to the nearest 10 g. Using m for the mass of the block in grams, write down the error interval for m.

10.3/5 of the students in a year group walk to school. 90 students walk to school. Work out the total number of students in the year group.

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

12.A restaurant adds a service charge of 15% to a bill of £120. Work out the service charge.

13.Using only 20p coins and 10p coins, and at least one of each, work out how many different ways there are to make exactly 60p. List the possibilities systematically.

14.A photography studio offers 4 backdrops and 3 outfits for a portrait session. The plain grey backdrop, one of the 4 backdrops, cannot be used with the formal suit outfit, one of the 3 outfits. Work out how many different backdrop-and-outfit combinations are possible.

15.Work out 35% of 180.