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This will Mess With Your Head. 3 MEN GO INTO A MOTEL. THE MAN BEHIND THE DESK SAID THE ROOM IS $30, SO EACH MAN PAID $10 AND WENT TO THE ROOM. A WHILE LATER THE MAN BEHIND THE DESK REALIZED THE ROOM WAS ONLY $25, SO HE SENT THE BELLBOY TO THE 3 GUYS' ROOM WITH $5. ON THE WAY, THE BELLBOY COULDN'T FIGURE OUT HOW TO SPLIT $5 EVENLY BETWEEN 3, SO HE GAVE EACH MAN A $1 AND KEPT THE OTHER $2 FOR HIMSELF. THIS MEANT THAT THE 3 MEN EACH PAID $9 FOR THE ROOM, WHICH IS A TOTAL OF $27, ADD THE $2 THAT THE BELLBOY KEPT = $29. WHERE IS THE OTHER DOLLAR? SEND THIS TO 5 PEOPLE AND THE ANSWER WILL APPEAR ON YOUR SCREEN.
First of all, let's clear up a misconception here. It doesn't matter how many people you forward this email to - the answer will never appear on your screen, unless someone decides to take pity on you and reply to your email.
Now, regarding the question of the three men and the bellboy, if this one stumps you, don't feel bad. I remember as a child puzzling over this one for a long time before I finally saw through the "trick". Believe it or not, the answer is exceedingly simple, and you don't need any advanced mathematics to figure it out.
What you've got to ask yourself is: If the men paid 27, and the boy took 2 from that, why in the world are you adding those two numbers instead of subtracting them? 27 - 2 = 25, which is the total amount paid. 27 + 2 is completely meaningless addition problem.
The thing that fools you into thinking it's a meaningful problem is the fact that the answer is close to 30, so you think it should add up to that. But there's no reason for that addition to add up to anything meaningful, because addition is not a meaningful thing to do with those two numbers in the context of the problem.
Also, the fact that there's an additional exchange (involving the man behind the desk) confuses the issue, and helps to distract you from the fact that the bellboy is really taking money from the guests.
Let me put it this way. If I gave you twenty seven apples, and someone took two away from you, would you then have 29? Of COURSE NOT! But that's exactly what the problem writer is trying to get you believe!
So when someone asks you "Why doesn't this add to 30?" just give them a puzzled look and say, "Why do you think it should?"
Added note: If you would like to see a similar problem click here: Guy Buying a Car.
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