the scale of a map is 0.5 inch : 40 miles. On the map, the distance between 2 cities is 5 inches. What is the actual distance between the two cities?

This is a proportion question.

0.5:40 miles : : 5:x

Translated into division you get 0.5/40 = 5/x Cross multiply

0.5 x = 40 * 5 combine the right

0.5x = 200 divide by 0.5

0.5x/0.5 = 200/0.5 Divide

x = 400

Answer: The two cities are 400 miles apart