This is a generalization of a puzzle that dealt with an equilateral triangle.
Assume three runners with the following speeds - 4.5, 6.2, and 8.7 meters/sec. They are at the corners of a triangle with sides lengths of 75, 49, and 63 meters.
They need to decide how to select the corner for each runner and a point in the triangle to which they run simultaneously and reach it at the same and shortest time.
Only compass and unmarked ruler could be used to derive a solution.