Coaching Centre
Metric units of length
Millimetres, centimetres, metres and kilometres, converting between them, and choosing sensible units.
The metric ladder
Convert (a) $3.5$ m to cm, (b) $4200$ m to km, (c) $65$ mm to cm.
(a) $3.5 \times 100 = 350$ cm
(b) $4200 \div 1000 = 4.2$ km
(c) $65 \div 10 = 6.5$ cm
Convert $0.08$ km to cm.
$0.08 \times 1000 = 80$ m
$80 \times 100 = 8000$ cm
cm in a metre
$100$
m in a kilometre
$1000$
Small unit to large unit
Divide.
Convert $3.5$ m to cm.
$\times 100$.
Convert $4200$ m to km.
$\div 1000$.
Convert $65$ mm to cm.
$\div 10$.
Convert $0.08$ km to cm.
$80$ m $= 8000$ cm.
Convert $2.5$ m to mm.
$\times 1000$.
Which unit suits the distance from Sydney to Parramatta?
It is about $23$ km.
Convert $125$ cm to m.
$\div 100$.
How many $25$ cm pieces can be cut from $10$ m of ribbon?
$1000 \div 25$.
New numbers every time. Keep going until you get five in a row.