They never told him where the crime scene was.
25/3 = 8.33333 so they actually paid 9.333333 dollars each
Good job. Actually another way to solve it is to subtract implying that you should mutiply throws people off. Obviously 5 dollars took away from 30 is 25, they got three dollars back, the bellhop got two, so looking at it like that there really is no missing dollar. Anyway this is a common question actually, its known as the missing dollar riddle.