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        riddles >> easy >> The Devil and the Loiterer.
        
(Message started by: rloginunix on Feb 19^th, 2014, 2:11pm)

Title: The Devil and the Loiterer.
Post by rloginunix on Feb 19^th, 2014, 2:11pm

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?

Title: Re: The Devil and the Loiterer.
Post by Grimbal on Feb 19^th, 2014, 4:09pm

[hide]a most unlucky number[/hide]

Title: Re: The Devil and the Loiterer.
Post by rmsgrey on Feb 20^th, 2014, 6:55am

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

Title: Re: The Devil and the Loiterer.
Post by rloginunix on Feb 20^th, 2014, 8:57am

Grimbal is correct. [hide]The Devil's dozen[/hide] 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 [hide]1[/hide] extra penny he/she would've had [hide]27[/hide] cents left. After the payback he/she would've had a [hide]26[/hide]-fold return on investment. Not bad for dealing with the Devil.
[/edit]

Title: Re: The Devil and the Loiterer.
Post by towr on Feb 20^th, 2014, 10:02am

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.
[hide]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.[/hide]

Title: Re: The Devil and the Loiterer.
Post by rloginunix on Feb 20^th, 2014, 11:45am

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.