In this activity, you will be solving a variety of problems using units of measurement.

You will need to be able to convert between different units of measurement.

Remember,

**milli- **means 1000th and **centi**- means 100th.

Also, **kilo** means 1000.

milli | 1000 mm | = 1 m |

1000 ml | = 1 l | |

1000 mg | = 1 g | |

centi | 100 cm | = 1 m |

100 cl | = 1 l | |

kilo | 1 kg | = 1000 g |

Other **useful conversions **to remember are...

**1 mm = 0.001 m**

**1 ml = 0.00 l **

**1 mg = 0.00 1g**

**1 cm = 0.01 m**

**1 cl = 0.01 l**

**1 g = 0.001 kg**

**Reminder:**

When solving a problem that uses more than one unit of measurement, always convert them so you are just **working in one unit.**

It's usually easier to work in the **smaller **unit and then convert back at the end if the question asks for the answer in the larger unit of measurement.

**Example:**

Zach pours **5 litres** of water into his paddling pool. He then removes **600 ml**. Finally, he adds another **50 cl.**

How much water is now in the paddling pool?

Give your answer in** litres.**

**Answer:**

Work in millilitres

5000 ml - 600 ml + 500 ml = 4900 ml

Convert back to litres by dividing by 1000.

**4.9 l **is in the paddling pool.

**Your turn!**