What is the scale on a map that shows two cities that are 400 mi apart as 2.5 in apart?

Cross multiply and solve for x.

400/2.5 = x / 1

To determine the scale on a map, you need to divide the actual distance between two points by the corresponding distance on the map. In this case, the actual distance between the two cities is 400 miles, and on the map, they are shown as 2.5 inches apart.

To find the scale, you can use the following formula:
Scale = Actual distance / Map distance

In this example, the actual distance is 400 miles, and the map distance is 2.5 inches. Plugging these values into the formula, we get:
Scale = 400 miles / 2.5 inches

To simplify the scale, we need to convert the units to match. Let's convert the miles to inches by using the conversion factor of 1 mile = 63,360 inches.

Scale = (400 miles * 63,360 inches/mile) / 2.5 inches
Scale = 10,572,800 inches / 2.5 inches

Finally, we divide the actual distance by the map distance to find the scale:
Scale = 4,229,120

So, the scale on the map is approximately 1:4,229,120, which means that one inch on the map represents approximately 4,229,120 inches (or 66.5 miles) in reality.