Measuring, Estimating and Units

Hong Kong

Stage 1 - Stage 3

Lesson

Estimating length is an important life skill. Not only does it help when you want to have a good idea of how far away something is, or how long, wide or tall some object could be. It is also important in common practical circumstances like moving furniture into a room, how much wrapping paper you might need to wrap a present, or how far apart to plant your seedlings in the vegetable patch.

There are two parts to good estimations involving length:

- Know what the best units of length would be to use
- Be able to estimate an appropriate size.

To get good at these, try and find some baseline lengths that are familiar to you. For example, ask yourself:

*What common everyday object do I know that is about 1cm or 1m long?**How far is it from my house to the end of the street?*

Then, when you need to estimate you could think about the estimation in terms of distances you are familiar with.

Choose the best estimate for the length of a classroom.

$4$4 metres.

A$60$60 metres.

B$100$100 metres.

C$10$10 metres.

D

Estimate the height of a desk.

$0.11$0.11 mm

A$110$110 mm

B$1.1$1.1 metres

C$1100$1100 cm

D