Brain Teaser
Three friends check into a motel for the night and the
clerk tells them the bill is $30, payable in advance. So,
they each pay the clerk $10 and go to their room.
A few minutes later, the clerk realizes he has made an
error and overcharged the trio by $5. He asks the
bellhop to return $5 to the 3 friends who had just
checked in. 
The bellhop sees this as an opportunity to
make $2 as he reasons that the three friends would
have a tough time dividing $5 evenly among them; so
he decides to tell them that the clerk made a mistake
of only $3, giving a dollar back to each of the friends.
He pockets the leftover $2 and goes home for the day!
Now, each of the three friends gets a dollar
back, thus
they each paid $9 for the room which is a total of $27
for the night.
We know the bellhop pocketed
$2 and
adding that to the $27, you get $29, not $30 which
was originally spent.
Where did the other dollar go????
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