A map scale is given as a ratio

Examples of map scales

1 cm measured on the map is 1000 000 cm, or 10 km, in real life.

1 cm measured on the map is 50 000 cm, or 0.5 km, in real life.

1 cm measured on the map is 250 000 cm, or 2.5 km, in real life.

Examples

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?

map |
: | Real life |

1 | : | 1000 000 |

10 | : | * |

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

Real life |
: | map |

0.5 km | : | 1 |

45 km | : | * |

solving using unitary direct proportion

solving using vedic maths

1:0.5 ::x: 45

or,

By the Rule of Three