How_To_Be_Good_At_Math

MEASUREMENT • LENGTH MEASUREMENT • LENGTH 161

HEIGHT (cm)

0

10

20

30

40

50

60

Take a look at this dog.

It’s 60 cm tall.

There are 100 cm in 1 m

and 10 mm in 1 cm.

We can easily change

this height into m, by

dividing it by 100. So, the dog

is 0.6 m tall.

Centimetres and millimetres

Metres and kilometres are great for

measuring big things but less useful for

measuring things that are much smaller.

We can use units called centimetres and

millimetres to measure shorter lengths.

We can even change

this height into mm,

by multiplying it by 10. This

means the dog is 600 mm tall.

We usually use mm to

measure much smaller

things, like the bumblebee

buzzing beside the dog. The

bumblebee is 15 mm long.

Converting units of length

Length units are easy to convert. All we need

to do is multiply or divide by 10, 100, or 1000.

5000 mm 500 cm 5 m 0.005 km

To convert mm to cm, we

divide by 10. To convert cm

to mm, we multiply by 10.

To convert cm to m, we

divide by 100. To convert m

to cm, we multiply by 100.

To convert m to km, we divide

by 1000. To convert km to m,

we multiply by 1000.

Cent

imetres^ to^ millimetre

s M

etres^ to^ centimetres

K

ilometres^ to^ metres

÷ 10 ÷^100 ÷ 1000

× 10 × 100 × 1000

Mill

imetres

to centimetre

s Centime

tres to metres

(^) M
etres to kilometres
Length, width, height,
and distance are
all measured using
the same units.
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