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Friday Puzzler -- String Theory (1 of 2)

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Friday Puzzler -- String Theory (1 of 2)

#1

Friday Puzzler -- String Theory (1 of 2)

Alex Y

Well, not really string theory, but it's fun to pretend to be able to understand that! This is another from Click and Clack(RIP).

You have two pieces of string, both 4' long. Each string has the property that if you light one end, it will burn up completely in one minute. However, the strings do not burn at a constant or even a predictable rate. I.e., one of the stings may burn up 2' in the first 10 seconds, 1' in the next 30 seconds, and the last foot in 20 seconds. And the other string may burn in a different pattern, just finishing in one minute.

Given those two strings and a zippo lighter, how can you measure 15 seconds?

Re: Friday Puzzler -- String Theory (1 of 2)

#2

Kent B

Re: Friday Puzzler -- String Theory (1 of 2)

Kent B

All at the same time, light both end of string#1 and light 1 end of string #2

String #1 will flame out at 30 seconds, somewhere along its length. At that instant, lite the remaining end of String #2, which has 30 seconds gone, and 30 seconds left to go.

String #2 will flame out 15 seconds after you light its second end.

I'm here all week. Remember to tip your waitress.

Re: Friday Puzzler -- String Theory (1 of 2)

#3

Very Good!

Alex Y

That didn't take long!

Second string problem coming later tonight.

Re: Friday Puzzler -- String Theory (1 of 2)

#4

Kent B

Re: Very Good!

Kent B

42

Re: Friday Puzzler -- String Theory (1 of 2)

#5

Re: Very Good!

Alex Y

The Ultimate Answer to Life, the Universe and Everything!

Re: Friday Puzzler -- String Theory (1 of 2)

#6

Re: Very Good!

Ed in Leaside

Three and a half

👍 This page answered my questions

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