Emilia is a micro-baker who bakes artisanal bread and sells it to customers from her home.
She finds that her customers buy more loaves when she charges less for each loaf. If she charges p dollars for each loaf, she can sell 255 - 15p loaves per month. This means her monthly revenue is p(255 - 15p) dollars. She uses $3 in ingredients to make each loaf, and she spends $195 a month to ship and deliver all of the loaves. This means that her monthly costs are 3(255 - 15p) + 195 dollars. Therefore, if Emilia charges p dollars for each loaf, her monthly profit in dollars will be p(255 - 15p) - (3(255 - 15p) + 195) dollars.
This expression can be simplified to -15p? + 300p - 960 and then written in factored form as
-15(P - 4)(P - 16).
What do the numbers 4 and 16 represent in the expression?