If then .
That is the nonsense of this question.
i was asked this puzzle today
three guys go to a hotel the man there says its 30$ a nite so they each give him 10$
then the man comes back to them and says i made a mistake its 25$ a night he gives each of them 1$ back and says i can't make change for the last 2$ so they each payed 9$ 3x9 is 27 plus the 2 the man kept is 29 where is the other dollar to make 30$ and or way does the math work one way and not this way
i know there is something i don't get or do not know of so take it ez on im an old guy
OK, I'll be a bit serious... no, it's not easy for me
As others have said, this is a pretty famous problem, and you may well have already Googled the solution. The answer is that the numbers are added incorrectly.
But the numbers are fine. Consider: when all is said and done, the room is $25. They tipped the bellhop $2. $25 plus $2 is the $27 total paid, or $9 per man.
Suppose the bellhop had made a really big error and said the room is $16 per night, not $30. Okay, so he gives each man $4 back, and says I cannot make change for the $2 i have left. They let him keep it.
Using these numbers, the problem would have been worded something like:
"So each man paid $6. $6x3 is $18 plus the $2 the bellhop kept, which is $20. Where is the missing $10 to make $30?"
...and that question will likely be pondered far less. A much bigger error causes one to consider sooner that something is amiss.
The problem has stuck since the "difference" using this funny reasoning and the numbers it does is only $1. When it gets bigger than that, as it just did when we used different numbers, the faulty addition is easier to see...
$30 paid, $1 each given back from the bellhop:
$9 each plus $1 each in their pocket plus $2 to the bellhop: = 27+3+2 =32
$30 paid, $2 each given back from the bellhop:
$8 each plus $2 each in their pocket plus $2 to the bellhop: = 24+6+2 =32
$30 paid, $3 each given back from the bellhop:
$7 each plus $3 each in their pocket plus $2 to the bellhop: = 21+9+2 =32
$30 paid, $4 each given back from the bellhop:
$6 each plus $4 each in their pocket plus $2 to the bellhop: = 18+12+2 =32
and so on.
In other words, where
c=change given back
3*r + 3*c +2
But, r+c is always 10. Thus,
3*(10)+2 = 32.
Still, that's what a to-remain-nameless former U.S. President would call "Fuzzy Math."