The Chain Smokers in our neighborhood are revered for their magical ability. They can use five cigarette butts to make a full cigarette. One day, they collected a 1000 cigarette butts. How many cigarettes can they make, at maximum?

Here's something pre-, THE ANSWER IS NOT 200

  • $\begingroup$ This looks like a math problem rather than a real puzzle $\endgroup$ – Sid Sep 2 '16 at 16:18
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    $\begingroup$ I think it's fair to call it a puzzle, but it's a really old puzzle... $\endgroup$ – Gareth McCaughan Sep 2 '16 at 16:19
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    $\begingroup$ @GarethMcCaughan Pretty sure, some similar puzzle would be present in the archives of this site.... This is a pretty famous one, even for kids..., there you go... puzzling.stackexchange.com/questions/33289/… $\endgroup$ – Sid Sep 2 '16 at 16:21

They make

200 cigarettes from the 1000 butts, then
40 cigarettes from the resulting 200 butts, then
8 cigarettes from the resulting 40 butts, then
1 cigarette from the resulting 8 butts,
at which point they have four butts left and can't go further.

So the number is


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  • $\begingroup$ You've got the cigar. $\endgroup$ – Aravind Suresh Sep 2 '16 at 16:19

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