The Cook



You are a cook in a remote area with no clocks or other way of keeping time other than a four-minute and a seven-minute hourglass. On the stove is a pot of boiling water. Jill asks you for a nine-minute egg, and you know she is a perfectionist and can tell if you undercook or overcook the egg by even a few seconds. How can you cook the egg for exactly 9 minutes?

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The Strange 2 Seconds



Noemie puts her coffee into the microwave, as she does every morning, for exactly 2 minutes. When the microwave goes off, she opens the door, but then closes the door again and sets the microwave for 2 more seconds. What good would 2 more seconds be?

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