Two trains travel directly toward each other. One of the trains travels at a rate of 12 km/h while the other travels at a rate of 20 km/h. When the trains are 72 km apart, a conductor at the front of one of the trains releases the insane pigeon Hyde. Hyde flies first from the slower of the two trains to the faster train at which point Hyde doubles back toward the slower train. Hyde continues to fly back and forth between the trains as they approach, always at a constant speed of 48 km/h. Assuming the trains never change speed until they meet and magically stop, how many kilometers has Hyde flown when the trains meet?
Note that every hour...the trains close the distance between them by [ 12 + 20 ] = 32 km
So.....the time until they meet = 72 / 32 = 18 / 8 = 9 /4 hrs
Since "Hyde" flies constantly during this time....the distance he covers is
Rate * Time = Distance
48 * (9/4) =
(48/4) * 9 =
12 * 9 =