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Numbers, units and arithmetic

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# 2.3 Measuring mass

The basic SI unit for mass is the kilogram, symbol kg

The tonne (t) which is equivalent to 1000 kg and is a metric unit is often used alongside the SI units.

The animation below illustrates how to convert between the most commonly used units of mass, the metric tonne (t); the kilogram (kg); the gram (g); the milligram (mg) and the microgram (μg).

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For example, to convert 480 kg into t, divide by 1000.

So 480 kg = 480 ÷ 1000 t = 0.48 t.

Try some yourself – use the calculator to type in the amount and then choose the units you want to convert. Then choose the operation (multiply or divide) and the factor. Then select check to see if your answer is correct.

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