05/02/2013 - From A to B (***)

This puzzle is rated 3 star (hard).

Description

A bike travels downhill at 20 mph (miles per hour), on the level (flat road) at  15 mph, and uphill at only 12 mph. The bike takes 4 hours to travel from town A to town B. The return trip takes 4 hours and 40 minutes. 

Puzzle
Find the distance between the two towns.

Check the solutions page for the correct answer.