Basic, GCSE(F),

The three common metric units are **metre** for length, **litre** for capacity and **gram** for mass.

Metric units are based on powers of 10, and the metric units (metre, gram, litre) are prefixed to indicate which power of 10 is being used:

**milli** means a thousandth (`frac(1)(1000)`)

**centi** means a hundredth (`frac(1)(100)`)

**kilo** means a thousand

**Length**

1 kilometre (km) = 1000 metres (m)

1 metre (m) = 100 centimetres (cm)

1 centimetre (cm) = 10 millimetres (mm)

**Mass**

1 tonne (t) = 1000 kilograms (kg)

1 kilogram (kg) = 1000 grams (g)

**Capacity**

1 litre (*l*) = 1000 millilitres(*ml*)

**Volume**

1 cm^{3} = 1 millilitre (*ml*)

To convert between amounts, set up a small table for the conversion. On the first line, show the conversion rate. On the second line, put in the value to convert.

1. Dylan is putting up a shelf in an alcove. The alcove measures 1058mm. The shelf is 103cm long. Dylan reckons that the shelf can be up to 4cm smaller than the alcove. Will the shelf fit?

Answer: Yes

Change the alcove from mm to cm:

cm | --> | mm |
---|---|---|

1 | x | 10 |

1058 ÷ 10 = 105.8 | 1058 |

Work out the smallest size the shelf can be: 105.8 - 4 = 101.8cm. The shelf is larger than the minimum and smaller than the alcove, so it will fit.

2. Mia is measuring out some liquid for a chemistry experiment. She needs 520cm^{3}. What is this in litres?

Answer: 0.520 litres

Change cubic centimetres to millilitres: 520cm^{3} = 520*ml*.

litre | --> | millilitre |
---|---|---|

1 | x | 1000 |

520 ÷ 1000 = 0.520 | 520 |

Going from millilitres to litres is a division: litres.

Our iOS app has over 1,000 questions to help you practice this and many other topics.

Available to download free on the App Store.

Available to download free on the App Store.