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…
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…
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…
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…
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…
