Question

Use scale of 18mm=1km to calculate the total length of the trail run. Hint use straight line distance between points and multiply with 1,2

Answer 1

Alright. 18 mm contain 1 km, then 1 mm contains 1/18 of 1 km. Therefore, if the total distance of the trail run on a map is 234 mm, the real distance in km will be

$$D=234\cdot1/18=13\text{ km}.$$