A map scale is given as a ratio
Examples of map scales
1:1 000 000
1 cm measured on the map is 1000 000 cm, or 10 km, in real life.
1:50 000
1 cm measured on the map is 50 000 cm, or 0.5 km, in real life.
1:250 000
1 cm measured on the map is 250 000 cm, or 2.5 km, in real life.
Example
The distance from Dogstown to Catsville is 10cm on a map
which has a scale of
1 : 1000 000.
How far is this distance in real life?
In real life , this is 10 x 1000 000 = 10,000 000 cm
Converting
10,000 000 cm = 100 000 m = 100 km
The distance from Dogstown to Catsville is 100 km
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The distance from Mousehole to Catsville is 45km.
How far is this distance on a map which has a scale
of 1 : 50 000 ?
1 cm measured on the map is 50 000 cm, or 0.5 km, in real life
solving using unitary direct proportion
solving using vedic maths
1:0.5 ::x: 45
or,
By the Rule of Three
© Alexander Forrest