Question

The scale on a map is 1:20000.

The area of the lake on the map is 1.6 square centimetres.
Calculate the actual area of the lake.
Give your answer in square metres.

Answer 1

1.6cm² · 20,000² = 1.6cm² · 200,000,000 = 320,000,000cm²

1m = 100cm therfore 1m² = 100² cm² = 10,000cm² therefore 1cm² = 0.0001m²

320,000,000cm² = 320,000,000 · 0.0001m² = 32,000m²

Answer: 32,000m²