Systems of Measurement

Most of the world now uses the metric system of measurement. In the UK metric measurements have been taught in schools since the early 1970’s; however imperial measurements are still used in some cases. We therefore have to know how to convert between metric and imperial measurements.

The Metric system

The metric system has almost universally been adopted as it is much easier to calculate accurately as all metric measurements are based on units of 10.

Milli – means one thousandth (or 1/1000)

Centi means one hundredth (or 1/100)

Kilo means one thousand (1,000)

Metric Measurements

Length is typically measured in:

Centimetre (cm) = 10mm
Metre (m) = 100cm
Kilometre (km) = 1,000m

Mass is measured in:

Kilogram (kg) = 1,000 grams

Tonne = 1,000kg

Volume is measured in:

Litre = 1,000ml

1,000 litres = 1m3

Imperial Measurements

Length is measured in:

1 foot = 12inches

1 yard = 3 feet

1 mile = 1760 yards

Mass is measured in:

1 pound = 16 ounces

1 stone = 14 pounds

1 ton = 160 stones

Volume is measured in:

1 gallon = 8 pints

Converting Metric and Imperial Units

As some imperial units are still in use today you do need to know how to convert them to metric and vice versa. The conversion rates below have been rounded to 2 decimal points.

Kilometres and Miles:

Miles to km - Multiply by 1.61

km to Miles - Multiply by 0.62

Kilograms and Pounds:

kg to Pounds - Multiply by 2.20

Pounds to kg - Multiply by 0.45

Litres and Gallons:

Litres to Gallons - Multiply by 0.22

Gallons to Litres - Multiply by 4.55

Metres and Centimetres to feet and inches:

Inch to cm - Multiply by 2.54

cm to Inch - Multiply by 0.39