Mr. Green went for a trip. Twenty percent of his trip he traveled on the bus. How long was Mr. Green's trip, if he covered by bus 15 miles?

The whole journey was 100%

He traveled part of the journey by bus which was equivalent to 20% of the journey. The distance traveled by bus is 15 miles. Therefore;

the total distance will be (15/20) * 100 = 75 miles

The trip was therefore 75 miles long

Solution: 20% of travel by bus which is equivalent to 15 miles.

20% of total = 15 miles

Then, 1% = 15/20

And, 100% = (15/20) * 100 = 75

The trip for which Mr. Green went was 75 miles.