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- Units, conversions and scale
Units, conversions and scale
Converting between units, and using scales on maps and drawings, are everyday maths skills that appear on every paper.
Metric conversions
1 km = 1000 m, 1 m = 100 cm, 1 cm = 10 mm
1 kg = 1000 g, 1 litre = 1000 ml
Area: 1 m2 = 10 000 cm2 (100 × 100)
Volume: 1 m3 = 1 000 000 cm3, and 1 cm3 = 1 ml
1 kg = 1000 g, 1 litre = 1000 ml
Area: 1 m2 = 10 000 cm2 (100 × 100)
Volume: 1 m3 = 1 000 000 cm3, and 1 cm3 = 1 ml
Scale drawings and maps
A map scale of 1 : 50 000 means 1 cm on the map is 50 000 cm in real life, which is 500 m.
Multiply map lengths by the scale, then convert units.
Multiply map lengths by the scale, then convert units.
Converting with a rate
Use a given rate: £1 = 1.17 euros. €58.50 ÷ 1.17 = £50.
Check the answer makes sense: euros to pounds should give a smaller number.
Check the answer makes sense: euros to pounds should give a smaller number.
On a 1 : 25 000 map, two towns are 8 cm apart. How far apart are they in km?
- 8 × 25 000 = 200 000 cm
- 200 000 cm = 2000 m
- = 2 km
Answer: 2 km
Learn the metric conversions; square them for area and cube them for volume. Multiply map distances by the scale, then convert to sensible units.
Check you have got it
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