What is mass?
Mass is a measure of how heavy things are. We often use the term weight instead.
In the metric system, mass is measured using grams, kilograms and tonnes.
There are 1,000 grams in 1 kilogram, and 1,000 kilograms in 1 tonne.
Look at this diagram that you can use to help you convert between the three units:
If we have a quantity measured in kilograms and we want to change it to grams, how do we do this?
We want the arrow pointing from kg to g so we multiply by 1,000.
Change 56 kg into g:
56 x 1,000 = 56,000
So 56 kg = 56,000 g
And if we want to change a quantity from kg to tonnes? We're going the opposite way, so we divide by 1,000.
Change 450 kg into tonnes
450 ÷ 1,000 = 0.45
So 450 kg = 0.45 t
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