Two horses approach each other along the same country road, one walking at 5.5 km/h and the other at 4.5 km/h. When the horses are 10 km apart, a horsefly leaves one horse and flies at 30 km/h to the other, No sooner does the fly reach that horse than it turns around and returns to the first horse. If the fly continues to fly back and forth between the approaching horses, how far has the fly flown when the horses meet?

Question

phi · Answer

The trick is to find how long the horses walk until they meet.

then use  rate*time = distance to find how far the fly has gone  (this assumes the fly loses zero time in turning around as it zips back and forth)

skullpatrol · Answer

@phi  I think the hardest part of this problem is to not try and add up the individual path lengths.

dan815 · Answer

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