Question

If on a scale drawing 5 inches represents 80 feet, then 3/4
inch would represent how many feet?

Answer 1

Use ratios to solve this problem. There are various ways to write ratios; I prefer that we compare apples to apples and oranges to oranges. Thus, the first ratio would be that of 5 inches to 3/4 inch; the second ratio would be 80 feet to x.

Set these two ratios equal to each other.
Cross multiply to eliminate the fractions.
Solve the resulting equation for x.
Write x with "feet" as units of measurement.