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Measuring mass

Mass is a measure of how heavy something is. Scales can be used to measure mass.

A set of scales

Metric units of mass

Mass is measured in grams (g), kilograms (kg) and tonnes. These are known as metric units of mass.
1 kg = 1000 g
1 tonne = 1000 kg

Remember when estimating mass:

  • 100g is about the mass of a small apple.

  • 1 kg is the mass of a bag of sugar or a litre of water.

Imperial units of mass

Ounces and pounds are old units of mass. These are known as imperial units but are not now commonly used in maths.
There are 16 ounces in a pound.
An ounce is roughly equal to 25 grams.
A pound (454g) is equal to just under half a kilogram (500 g).

More from Measures:

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