How do I convert between units for lengths?

• For metric units, conversion can be done by simply multiplying or dividing by powers of 10
• You need to know the basic conversions
  • 1 cm = 10 mm
  • 1 m = 100 cm
  • 1 km = 1000 m
• To decide whether to multiply or divide you need to ask yourselves does the number of units increase or decrease
  • e.g. The number of mm is 10 times bigger than the number of cm so mm = cm × 10
• You can do the conversion in stages
  • First convert kilometres into metres then metres into centimetres
• If you are given an imperial conversion (such as miles to kilometres) then you can use ratios to help with the conversions
  • There are 5 miles in 8 kilometres so to find how many miles are in 13 kilometres you would solve 

How do I convert units for mass?

• For metric units, conversion can be done by simply multiplying or dividing by powers of 10
• You need to know the basic conversions
• 1 g = 1000 mg
• 1 kg = 1000 g
• 1 tonne = 1000 kg
• If you are given an imperial conversion (such as pounds to kilograms) then you can use ratios to help with the conversions
• e.g. There are 2.2 pounds in 1 kilogram so to find how many kilograms are in 10 pounds you would solve 

How do I convert units for volume/capacity?

• For metric units, conversion can be done by simply multiplying or dividing by powers of 10
• You need to know the basic conversions
• 1 l = 1000 ml
• 1 cl = 10 ml
• 1 ml = 1 cm ³
• If you are given an imperial conversion (such as pints to litres) then you can use ratios to help with the conversions
• e.g. There are 1.75 pints in 1 litre so to find how many litres are in 5 pints you would solve