Question

Note: this is ratio math. On a map, 1 inch equals 19.8 miles. If two cities are 3.5 inches apart on the map, how far are they actually apart?

Answer 1

Ratios are relations between two variables. A scale on a map is a ratio, it relates the distances on the map to the distances in the real world. In this case, 1 inch on the map is equivalent to 19.8 miles in the real world, so to find the distance we need to multiply the number of inches on the map by 19.8, as shown below:

$\text{ real distance}=3.5\cdot19.8=69.3\text{ miles}$

The real distance between the cities is 69.3 miles.