Nothing you can do with math applies after
reading this. I think that all structural calculations I have ever done are now invalid because of the flawed system. The world is about to end.

Three guys in a hotel call room service and order two large Pizzas. The delivery boy brings them up with a bill for exactly $30.00. Each guy gives him a $10.00 bill, and he leaves.
That's fact! When he hands the $30.00 to the cashier, he is told a mistake was made. The bill was only $25.00, not $30.00. The cashier gives the delivery boy five $1.00 bills and tells him to take it back to
the 3 guys who ordered the pizza. That's fact!

On the way back to their room, the delivery boy has a thought. These guys did not give him a tip. He figures that since there is no way to split $5.00 evenly three ways
anyhow, he will keep two dollars for himself and give them back three dollars. OK! So far so good!

He knocks on the door and one fellow answers. He explains about a mix up in the bill, and hands the guy the three dollars, and then departs with his two-dollar tip in his pocket.
Now the fun begins!

Remember $30-$25=$5 Right?
$5-$3=$2 Right?
So what's the problem?
All is well, right? Not quite. Answer this: Each of the three guys originally gave $10.00 each.
They each got back $1.00 in change. That
means they paid $9.00 each, which times three is $27.00. The delivery boy kept $2.00 for a tip. $27.00 plus $2.00 equals $29.00.

quote:

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Originally posted by Crysdon:
You think you can count ????

They each got back $1.00 in change. That
means they paid $9.00 each, which times three is $27.00. The delivery boy kept $2.00 for a tip. $27.00 plus $2.00 equals $29.00.

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In effect, you double-counted the tip right here. The $9 each includes the tip, then you've counted it again.

I get paid to find stuff like this, but I don't usually waste my time unless it's over ten thousand dollars.

quote:

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Originally posted by Crysdon:
You think you can count ???? [etc.]

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I heard a much more baffling puzzle once:

The neighbouring states of Northia and Southia have always been on friendly terms; their common border is open, and their currencies (the Northian and Southian Dollars) completely interchangeable; $N1=$S1.

Recently, however, there has been cooling of the relationship, and the day before yesterday the Northian Finance Minister went on TV to announce that henceforth $S1 would be regarded in Northia as only being worth N90c.

Yesterday, predictably, the Southians retaliated by replying that $N1 would only be worth S90c.

Today, a young man who lives in a town straddling the border set out with $N1. With this he went into a Northian barber, bought a 10c razor, and was given a $S1 note in exchange. He then crossed the road to a barber in Southia, bought a 10c packet of razor blades, and was given a $N1 note. He then went home.

He has the razor, the blades, and the money he set out with, but the two barbers also have their money. So, who paid for the razor and blades?

Go figure...

quote:

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Originally posted by ROBERT.BAK:

So, who paid for the razor and blades?

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Hah. Cute. The trick lies in the separate exchange rates. Because the exchange rate in Northia is not the same as the exchange rate in Southia, value is lost whenever Northian currency is spent in Southia, and vice versa.

which was kindly posted to the ML today.