Can you find the missing dollar

3 guys went out to eat, the waitress came back with the bill it was $30 even. So they all threw in $10 each. As they were leaving the waitress said she over-charged them, the bill was actually $25. Since it would be hard for the guys to split $5 evenly amongst them, they told her to just give them back $1 each and keep $2 for a tip.
So she did.
So in all, the guys each paid $9 -9x3 = $27
and the waitress kept $2 - $27+$2=$29
What happened to the other dollar of the original $30 they gave her?

i'm trying to figure it out but cant ha

3 guys went out to eat, the waitress came back with the bill it was $30 even.
So they all threw in $10 each.
As they were leaving the waitress said she over-charged them, the bill was actually $25.
Since it would be hard for the guys to split $5 evenly amongst them,
they told her to just give them back $1 each and keep $2 for a tip.
So she did.
So in all, the guys each paid $9 ----> 9 x 3 = $27
and the waitress kept $2 ----> $27 + $2 = $29
What happened to the other dollar of the original $30 they gave her?
Amount paid to waitress ----> $25 + $2 = $27
Each had paid only $9 -----> 9 x 3 = $27
Where the hell is a dollar missing?!!!

Adding $27 to $2 doesn't make sense. The $27 already includes the $2 that the waitress kept. You should subtract $2 from $27 to get $25: the actual cost of the bill. Or, add $27 to $3 (the total change given to the three customers) to get $30: the amount originally paid.