Wednesday, January 7, 2009

$30 = $29?!?!?!

Three men dine in a restaurant. The total bill is $30 and each man hands the waiter $10. Later, the cashier realises that there has been a mistake and the actual bill is $25. The waiter returns the change of $5. Since it's hard to distribute $5 among the three people, the three men decided to give the waiter a $2 tip and each men got back $1 change.

This means that each man has paid $9, making it a total of $27. Including the $2 tip, the 3 men has paid in total $29. But didn't they pay $30 in the first place? Where has that $1 gone to?!?!

Try and explain this. The first correct answer to reach my email will get a small prize!

Update 08 Jan 2009 9:22pm: Thanks for all your participation! After 1 day, one of my Sec 2 student has emailed me with a correct and reasonable explanation. To see her answer, select the blank space below with your mouse cursor.

Well, in the first place if 3 men paid $9, it becomes $27. FROM THE
$27, $2 already has been paid as a tip! Why do we have to then add $2 yet
again!. For example, from the $30 we remove $25, leaving us with $5. that $5 had
$2 as a tip. so we add $2 to $25, isn't that $27? and $27 divided by 3 is $9!
Each man paid $9! So, basically, you all have confused yourselves, by adding
another $2 to $27 when it already has been there, and the remaining $3 was the
change given to them:)

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