Often learning curves display a pattern where the average cost of production falls by the same percentage every time cumulative output doubles. Suppose a relatively new firm calculated its average cost of production to be $15.00 when it had produced its 100th unit of output. Then when cumulatve output reached 200 units, its average cost had fallen to $12.00. Assuming this pattern continues, its average cost should drop to about $ by the time the firm's cumulative output reaches 800 units. (Enter your response as a real number rounded to two decimal places.)