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- The bird and the train 3 answers
John and Peter are two friends living in two nearby villages 15km apart.
One day they arrange to meet, but little do they know, a “flies marathon flyer”, an irritating fly, decides to play a game.
John walks with 7km/h speed. Peter walks with a 8km/h speed.
The fly flies at a 13.125 km/h speed.
If they all start moving together, and the fly moves between each other's nose back and forth, can you find how long a “flies marathon” is?