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Puzzle for Today

Puzzle No. 392 – Thursday 10 January

From Singapore I fly ten hours due west to Equatorial Guinnea, a distance of 10,000 kilometres. From there I fly 10 hours due North. How long is my flight from there back to Singapore?

Today’s #PuzzleForToday has been set by Dr Hugh Hunt from Cambridge University Engineering Department

10 hours

The circumference of the Earth is 40,000km so the 10-hour flight is one quarter of the Earth's circumference. Singapore is on the equator as is Equatorial Guinnea. 10 hours North from both places gets you to the North Pole.

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