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Topic: The Devil and the Loiterer. (Read 1436 times) |
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rloginunix
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The Devil and the Loiterer.
« on: Feb 19th, 2014, 2:11pm » |
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The Devil and the Loiterer.
The Devil to the loiterer:
- Every time you cross that bridge the money in your pocket will triple.
- What's the catch?
- After each bridge crossing just give me back 27 bucks.
- Deal!
After three bridge crossings the loiterer was left with empty pockets.
How much money did the loiterer have?
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Grimbal
wu::riddles Moderator
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Re: The Devil and the Loiterer.
« Reply #1 on: Feb 19th, 2014, 4:09pm » |
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a most unlucky number
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rmsgrey
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Re: The Devil and the Loiterer.
« Reply #2 on: Feb 20th, 2014, 6:55am » |
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If I were the loiterer, I'd have borrowed 51 cents from someone before crossing the bridge - and made at least 4 crossings before repaying them
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rloginunix
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Re: The Devil and the Loiterer.
« Reply #3 on: Feb 20th, 2014, 8:57am » |
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Grimbal is correct. The Devil's dozen as they also call it.
rmsgrey, are you proposing to borrow 51 cents on top of the amount of money the loiterer already has or you are assuming loiterer's pockets are empty to begin with?
[edit]
The way I see it, if the loiterer borrowed just 1 extra penny he/she would've had 27 cents left. After the payback he/she would've had a 26-fold return on investment. Not bad for dealing with the Devil.
[/edit]
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| « Last Edit: Feb 20th, 2014, 9:06am by rloginunix » |
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towr
wu::riddles Moderator
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Some people are average, some are just mean.
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Re: The Devil and the Loiterer.
« Reply #4 on: Feb 20th, 2014, 10:02am » |
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It still a lot better to not cross the bridge. Going from $13 to $0.26 is not such a good deal (though when dealing with the devil there are worse alternatives than losing a few bucks).
So you'll need to borrow more than 1 cent.
You need to borrow $0.50 to break even, so as rmsgrey suggests, you need an extra cent on top of that to make a profit. And with 4 trips you've made enough profit to repay that 51ct, and still make more profit by continuing to cross the bridge.
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| « Last Edit: Feb 20th, 2014, 10:02am by towr » |
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Wikipedia, Google, Mathworld, Integer sequence DB
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rloginunix
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Re: The Devil and the Loiterer.
« Reply #5 on: Feb 20th, 2014, 11:45am » |
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I see, borrowing vs having the money already.
Good observation, rmsgrey. I didn't think of it that way. I just rigged the numbers for a cheap thrill because it's a different thing I'm after.
The second problem in a series of three related ones is Swan Lakes.
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