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 MEN, 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?

30-5 = {3(10-1)} -2

Note the "-2"  The $2 should have been subtracted to get to the $25 Total on each side of the equation.  Pretty sneaky.