Riddles

Sent by Yusuf Umar

3 guys are looking for a place to stay so they find this motel... when they get in the clerk says there's one room left but he's not sure how much it costs and the men will have to wait for the manager to get back.... the clerk then says or you guys could leave 30 dollars here with me and either I'll bring back change or I'll come collect the rest in the morning.
The 3 guys leave 10 dollars each.......the manager comes and the room turns out to be 25 dollars so the manager gives the clerk 5 dollars to return to the 3 guys, the clerk then says but there's 3 guys how should I split it and the manager said well give each guy a dollar and keep 2 for yourself.

NOW!.....each guy spent 10 dollars, but got one back...which means they spent 9 dollars each, so 9x3=27 so the 27 dollars the guys spent plus the 2 the clerk kept equals 29 but the guys left 30....so where's the other dollar?