Converting between units

The table shows some of the most common units and their equivalents. Make sure you know these conversions.

Converting measurements
Length\[{1}~{km} = {1,000}~{m}\]\[{1}~{m} = {100}~{cm}\]\[{1}~{cm} = {10}~{mm}\]
Weight\[{1~tonne} = {1,000}~{kg}\]\[{1}~{kg} = {1,000}~{g}\]\[{1}~{g} = {1,000}~{mg}\]
Capacity\[{1}~{l} = {100}~{cl}\]\[{1}~{cl} = {10}~{ml}\]\[{1}~{l} = {1,000}~{ml}\]

Converting larger units to smaller units

To convert a larger unit to a smaller unit (eg \({m}\) to \({cm}\)), first check the number of smaller units needed to make \({1}\) larger unit. Then, multiply that number by the number of larger units.

Converting smaller units to larger units

To convert a smaller unit to a larger unit (eg \({cm}\) to \({m}\)), divide it by the number of smaller units which are needed to make \({1}\) larger unit.

curriculum-key-fact
To convert from a larger unit to a smaller one, multiply. To convert from a smaller unit to a larger one, divide.

Example

\[1~m = 100~cm\]

So, to convert from \({m}\) to \({cm}\) multiply by \(100\), and to convert from \({cm}\) to \({m}\) divide by \(100\).

For example:

\[3.2~m = 320~cm~(3.2 \times 100 = 320)\]

\[400~cm = 4~m~(400 \div 100 = 4)\]

Question

Convert the following to the units given in brackets:

a) \(5,120~g~(kg)\)

b) \(15~cl~(ml)\)

c) \(245~mm~(m)\)

a) \(5.12~kg\)

Remember that \(1~kg = 1,000~g\).

To convert from \({g}\) to \({kg}\), divide by \(1,000\).

b) \(150~ml\)

Remember that \(1~cl = 10~ml\).

To convert from \({cl}\) to \({ml}\), multiply by \(10\).

c) \(0.245~m\)

Remember that \(1~m = 1,000~mm\).

To convert from \({mm}\) to \({m}\), divide by \(1,000\).