Answer:
Direct proportion
Explanation:
We are given that 3 inches represents 50 miles on a map
We have to find the proportion can be used to find the actual distance represented by 5 inches on the map
In 3 inches = 5 miles
In 1 inch =

To find the 5 inches distance in miles we are multiplying by ratio

In 5 inches =
miles
After multiply then we get
5 inches =
miles
Hence, the direct proportion can be used to find the actual distance represented by 5 inches in miles on the map