Two Boats and width of the river - a geometric solution

The Problem

Two boats on opposite banks of a river start moving towards each other. They first pass each other 1400 meters from one bank. They each continue to the opposite bank, immediately turn around and start back to the other bank. When they pass each other a second time, they are 600 meters from the other bank. We assume that each boat travels at a constant speed all along the journey. Find the width of the river?


Change the distances of the meeting points of the boats from the shores. This geogebra applet solves the problem geometrically and displays the width of the river.