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Burning Rope Question (only one rope)


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Q: You have ONE rope. If you lit it from one end and allowed to go on till it reaches the other end, the total time the rope takes to get burnt is one hour. How do you use the rope to time 15 minutes?

I read this from a book and it looks a bit like a the classical "rope burning question". However, in the classical question (eg. https://tzookb.com/two-ropes-brainteaser), you are given two ropes where each rope takes an hour to burn from one end.

 In the book I read, however, you only have ONE rope, so I couldn't figure out how to time 15 minutes. Could anyone figure out a way to time 15 minutes with just one rope? Could there be a mistake in the book?

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How about...

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Since you have an hour worth of burn time, you need to keep 4 burn points going at all times.  Start both ends and some point in the middle, which will burn in two directions, burning.  This will start 4 points burning.  Once two burn points meet, choose a point in the middle of the remaining rope to start on fire to return it to 4 points burning.  Repeat until the rope is all gone.

 

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