Ferry Boat Solution

Two ferry boats ply the same route between ports on opposite sides of
a river. They set out simultaneously from opposite ports, but one is
faster than the other, so they meet at a point 720 yards from the
nearest shore. When each boat reaches its destination, it waits 10
minutes to change passengers then begins its return trip. Now the boats
meet at a point 400 yards from the other shore. How wide is the river?


A graphic solution in Python is at


A solution from Math Central