Numbers, units and arithmetic
Numbers, units and arithmetic

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Numbers, units and arithmetic

2.1.2 Try some yourself

Activity 15

Suggest appropriate units for each of the following:

  • (a) the age of the kitten when it is weaned;

  • (b) the distance between one train station and the next;

  • (c) the amount of one ‘active’ ingredient of a prescribed pill;

  • (d) the cost of leaving the light on continuously for 24 hours.


  • (a) The age of a young kitten would be measured in weeks or days.

  • (b) The distance between train stations could be measured in kilometres (or miles).

  • (c) The active ingredients of a pill are usually measured in milligrams.

  • (d) The cost of leaving a light on for 24 hours will vary according to the type of bulb and the price of electricity, but it is likely to be measured in pence.

Activity 16

Choose appropriate units for each of the following, using metric units where possible:

  • (a) your height;

  • (b) your weight;

  • (c) the length of time to boil an egg;

  • (d) the capacity of a large pan.


  • (a) Your height could be measured in metres, e.g. 1.55 m, or centimetres, e.g. 155 cm. It may be that you only know your height in feet and inches, e.g. 5 ft 1 in.

  • (b) Your weight might be given in kilograms, e.g. 58.06 kg, or perhaps in stones and pounds, e.g. 9 st 2 lb.

  • (c) The length of time to boil an egg is usually given in minutes, e.g. 3 min.

  • (d) Pans are described in terms of the amount of liquid they hold, measured in litres (or pints), e.g. a 2‑litre pan.


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