Light Bulbs

Rachel’s math club meets in a classroom at the end of a long hallway in her school. This long hallway is lit by a row of 100 light bulbs, each with a chain attached to it that toggles the light bulb on or off when pulled. One day, Rachel arrives…

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Wolf, Goat, Lettuce

Here’s a classic puzzle: Farmer Brown is taking his goods to market: a goat, a wolf, and a head of lettuce. There is a river on the way to the market. Ordinarily there would be a bridge spanning the river. But today the bridge has collapsed, and the only way…

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