Problem Math????????????

In an attempt to minimize the lines this year, the hayride operators decided to run 3 Flatbeds at a time. Initially, they use 20 bales of hay on each flatbed. They find that at the end of the each day they need to replace half of the hay on each of the flatbed's to be ready for the next day's buisness. How many total bales of hay will the hayride operators have used on the 3 flatbeds after they replenish the hay at the end of the fifth day of buisness?