Two trains and a fly
Two trains start 100 miles apart and head straight toward each other, each at 50 mph. A fly starting on one train flies at 75 mph, bouncing back and forth between the trains until they collide. How many miles does the fly travel in total?
Show hints (2)+
- Don't sum the bounces - find how long until the trains meet.
- Distance = fly speed × collision time.
Answer
Reveal answer →Final answer
75
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