P. 3888. A man is walking along a straight road from point A to point B with a uniform speed. Point O is on the perpendicular bisector of the line segment AB, and at O there is a man who is beating a drum. Another day another man is walking from A to B, with the same speed as the first man was walking, and plays the drum, while an observer listens at point O. In which case does the observer count more beats while the man moves from A to B? (The beating starts in both cases well before the man leaves A, and lasts at least until the man reaches B. The beating is uniform, its period is the same in both cases and much smaller than the time needed to walk from A to B.)
Deadline expired on 11 May 2006.