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Seven minutes with a 3 and a 5 minute glass

hourglassestiming

You have a 3-minute hourglass and a 5-minute hourglass. You need to time exactly seven minutes, and the clock starts the moment you first flip a glass.

Find the sequence of flips. You may flip a glass at any moment, including while it is still running, and the timing must be exact rather than approximate.

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Five plus two is seven. After the 5-glass finishes, is there a glass somewhere that has run for exactly two minutes?

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