A boy, a girl and a dog go for a 38 mile journey. The girl takes 16 minutes to walk a mile. The boy takes 15 minutes to walk a mile and the dog can trot a mile in 10 minutes. They also have a bicycle which only one of them (including the dog!) can use at a time. When riding, the girl can travel a mile in 6 minutes, the boy can travel a mile in 5 minutes and the dog can pedal a mile in 4 minutes (what a marvelous dog!). What is the shortest time in which all three can complete the trip?
Credit for problem goes to Dr. Kevin Wang (not sure if it’s by him or not).
Good luck. Post solutions as blog post or comment.