An **area** consists of a length multiplied by a width. The size of the length and the width are both measured using **linear** measurements, such as centimetres, metres, inches or feet. Because the calculation is a multiplication, the units are also multiplied together: multiplying 3cm by 5 cm gives 15 cm^{2}: note the ^{2} after the cm.

When calculating areas, both measurements must be in the same units before attempting the calculation.

A **Volume** is a measurement of length x width x height: the units are also multiplied together: 3cm x 4cm x 5cm = 60cm^{3}: note the ^{3} after the cm.

Volumes must also be calculated using the same measurement.

A tank containing fuel is 2m long, 1m wide and 1.5m high. What is the volume of the tank?

The calculation is 2 x 1 x 1.5 = 3.

Note that the answer is in *cubic* metres.

Answer: 3m^{3}

An advertising sign is being prepared. The sign is 1.2m wide by 45cm tall. It will be covered in a waterproof material. What area of waterproofing material will be required? Give the answer in square metres.

Convert 45cm to 0.45m, then calculate 1.2 x 0.45 to give 0.54.

Note that the answer is in *square* metres.

Answer: 0.54m^{2}

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