My pound has vanished

[Maudlettice]

From the builders merchant the other day 3 of us purchased a washbasin for the flat each paying �10 - a total of �30. Later the merchant found he had overcharged us by �5 and sent his driver round with it. The driver stole �2 and gave us back �3, which meant we had each paid �9. Three times �9 = �27, plus the �2 the driver pinched = �29. Where is the other �1?

[Elle]

There is no missing pound. The merchant was paid �25, the driver stole �2, and you got back �3, making a total of �30. I've seen this on AB before, only it was 3 men paying for a hotel room, and tipping the belboy with �2.

[robber1]

Hello Elle :-)

[Quizmonster]

Yes, Elle, this is just - as you say - the old USA bellboy problem in a new guise. Three men pay a hotel-bill of $30.00, giving $10.00 each. The desk-clerk realises he has overcharged by $5.00 and sends the bellboy back with that amount. He, however, steals $2.00 and gives the men just $1.00 each. Thus, they've paid $9.00 each = $27.00 and the bellboy's got $2.00, so where's the supposedly 'missing' $1.00?

This is really a 'problem' with the way the situation is worded, not a problem of arithmetic. The three men paid 27 for the room, but only if you add in the 2 the bell boy kept. That 2 should be subtracted from - not added to - the 27, which gives the room cost of 25. Looked at another way, the desk-man has 25, the bell boy has 2 and the men have 3, which equals 30, which is exactly where you started. The same applies to the washbasin situation.

[wildwood]

By that reasoning, you have eleven fingers. Count backwards 10,9,8,7,6, plus the 5 on your other hand makes 11.

[Elle]

Hello Robber 1. ;o)

[answerbok]

that old chestnut, :-)
So it's lateral thinkers at dawn is it? ok.

[Sixtusthe5th]

I have a doubt about your arithmetic, Q. Is it not a simple fact that each man paid $10, got back a $1 each, so each paid $9 and the total room cost was therefore 3x$9 = $27?

[Maudlettice]

Quite so, Six. Q has patted the answer into conventional arithmetic - the intention was to charge 25, add the stolen 2 plus the 3 returned and we are at 30. But does this explain that if you put three piles of 10 coins on the table, take 1 off each and put the stolen 2 to one side you have only 29?