Riddles

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Below and in the watch section, you’ll find the most insightful stories and videos. In the learn section, you’ll find learning guides to 55+ topics, from artificial intelligence to public speaking.

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…