Chapter 2 - Solving Equations - 2-8 Proportions and Similar Figures - Practice and Problem-Solving Exercises - Page 134: 18

1 inch: 70 miles

In order to describe the scale on the map, we put the distance on the map, then a colon, and then write the total distance. This gives us 2.5 inches: 175 miles. However, we need the first number to be one, so we divide both sides by 2.5 to get a scale of 1 inch: 70 miles.