Riddles

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Train Fly Problem

Two trains are on the same track a distance 100 km apart heading towards one another, each at a speed of 50 km/h. A fly starting out at the front…
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100 Light Bulbs

100 light bulbs are in a line, and all are turned off. Perform the following steps. (1) change the state of every bulb (IE turn them all on). (2) change…
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Three Hats

There are 3 prisoners in a room. Two are wearing red hats, and one is wearing black hat. Each prisoner can see all hat colors except his own. The prison…
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Monty Hall problem

The Monty Hall problem is a brain teaser, in the form of a probability puzzle, loosely based on the American television game show Let’s Make a Deal and named after…
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How Many Cars Will Get Stuck In Traffic?

There is a very long, straight highway with some number of cars (N) placed somewhere along with it, randomly. The highway is only one lane, so the cars can’t pass…