Question

On the scale drawing of a school playground, a triangular area has side lengths of 8cm,15cm and 17cm.if the triangular area on the playground has a perimeter of 120m,what is the length of it's longest side?

Answer 1

Perimeter of a triangle $P=a+b+c$

Where $a, b, c$ are the sides of the triangle..

Perimeter of the scale drawing is therefore $P=8cm+15cm+17cm=40cm$

The ratio of the scale drawing to the actual area is $40cm:120m=1cm:3m$

Longest side is 17cm therefore actual length is $(17cm/1cm)*3m=51m$