Discuss the below:
Q: Joan's pastries are freshly baked and sold at several shops throughout Houston. When they are a day old, they must sold at reduced prices. Each pastry sells for $11.00 and costs $5.30 to make. Each one not sold at the end of the day can be sold the next day for $2.10 as day-old merchandise. Assume that Joan always can sell all leftovers.