Benjamin:How big is this parking lot in our community?
Security guard: It has fifty parking spaces.
Benjamin: So you guys should be always busy.
Security guard: Why?
Benjamin: I bet it is always full of cars.
Security guard: Quite the contrary, sir. Plenty of the spaces here are free when people drive their cars out to work.
Benjamin: Ah…I see.
Security guard: We plan to rent some of them out at the hourly rates.
Benjamin: What is the hourly rate for a car like this?
Security guard: I am not sure. But it'll be at least ten yuan an hour.
Benjamin: How mush would it cost if someone parks here for one hour and ten minutes?
Security guard: That would be twenty yuan, sir. We charge only by the number of hours, no split of each hour.
Benjamin: That's expensive.