Choose the most appropriate unit of length for measuring objects (mm, cm, m, km)

Any unit 

You can actually use any unit of measurement to measure something, but it makes sense to use the unit of measurement that:

• helps describe how long something is, and
• makes it easier for you to measure something.

An insect that is $8$8 mm long is easy to imagine, but if someone told you it was $0.000008$0.000008 km long, it would be tricky to imagine just how long it was. Here's a guide showing when to use which unit of measurement.

Worked Examples

Question 1

Question 2

Question 3