Question

A father ,mother and a boy go for a 10 mile walk ,starting at a point A. The father and mother walk at 2 mph and the son at 4 mph . They also have a bicycle which only one of them can use at a time when riding either the father or mother can pedal at 12 mph while the boy can pedal at 16 mph . What is the shortest time in which all the three can complete trip ???

Answer 1

Two and a half hours