Final answer:
To calculate the actual distance between two cities based on a map scale, multiply the measured distance in inches by the scale factor. For example, if a map shows 3 inches between cities and the scale is 1/4 inch to 43 miles, then the cities are 516 miles apart.
Step-by-step explanation:
Finding the Actual Distance Based on a Map Scale
The question is about determining the actual straight-line distance between two cities. To find this distance, we use the scale provided on the map. For instance, if the map scale indicates that 1/4 inch equals 43 miles, and the two cities are measured to be a certain number of inches apart on the map, we can calculate the actual distance by multiplying the number of inches by the scale factor. This procedure involves basic arithmetic and an understanding of map scales, which is part of the mathematics curriculum typically covered in high school.
Let's apply this method to find the distance between San Francisco and San Diego, which is measured as 3 inches apart on the map. If 1/4 inch represents 43 miles, then one inch would represent 4 times 43 miles, which is 172 miles. Therefore, multiplying 172 miles by the measured distance of 3 inches on the map gives us the actual distance between the two cities. This operation is a straightforward multiplication: 3 inches times 172 miles per inch equals 516 miles.