ender516 wrote:Since no one has posted a puzzle in a while, and I think I got the right answer to "How many times can you subtract 5 from 135?", I will throw a new log on the fire:
I have four horses that I wish to transfer from point A to point B. Being of different ages and states of health, these animals can make the trip in 1, 2, 4, and 6 hours, respectively (regardless of whether I am riding one or not). For reasons known only to the Great Puzzler, I can only transfer a maximum of two horses at a time (say I ride one and lead the other). When travelling with two horses, naturally we are forced to go at the slower speed of the two. How long will it take to transfer all four horses from A to B?
14 hours?
Let's call the horses Gallop, Canter, Trot, and Walk (in order of fastest to slowest).
Leg 1, A to B: Gallop and Walk (6 hours)
Leg 2, B to A: Gallop (1 hour)
Leg 3, A to B: Gallop and Trot (4 hours)
Leg 4, B to A: Gallop (1 hour)
Leg 5, A to B: Gallop and Canter (2 hours)
Poor Gallop is going to have a heart attack after running for 14 straight hours, though.