Numbers, units and arithmetic

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# 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.

### Answer

• (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.

### Answer

• (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.

MU120_4M1

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