University Bakery makes three kinds of muffins - blueberry, banana nut, and chocolate chip. Demand for the three muffins are 20, 15 and 30 muffins per hour, respectively. University Bakery's production process can produce any muffin at the rate of 90 muffins per hour but 0.5 hours are needed to switch between muffins. During those switchover times, the process doesn't produce any muffins. The bakery wants to choose a production schedule that (i) cycles repeatedly through the three muffins, (ii) meets the required demand and (iii) minimizes the amount of inventory held. How many banana nut muffins should the bakery produce before switching over to another muffin? Report your answer as an integer