Problema Solution

A pizza shop makes $1.50 on each small pizza and $2.15 on each large pizza. On a typical friday, it sells between 70 and 90 small pizzas and between 100 and 140 large pizzas. The shop can make no more than 210 pizzas in a day. How many of each size pizza must be sold in order to maximize profit?

Answer provided by our tutors

let


x = the number of small pizzas sold

y = the number of big pizzas sold


it sells between 70 and 90 small pizzas


70 <= x <= 90


and between 100 and 140 large pizzas


100 <= y <= 140


the shop can make no more than 210 pizzas in a day


x + y <= 210


the profit is determined by


F(x , y) = 1.50x + 2.15y


lets draw the graph of the system of inequalities


70 <= x

x <= 90

100 <= y

y <= 140

x + y <= 210


click here to see the graph


Click to see all the steps



look at the graph and find the notice the corner points!


there are 4 corner points and we calculate F(x ,y) for each point to find the maximum value (the biggest value for F):


(70, 100)


F(70, 100) = 1.5*70 + 2.15*100 = $320


(90, 100)


F(90, 100) = 1.5*90 + 2.15*100 = $350


(90, 120)


F(90, 120) = 1.5*90 + 2.15*120 = $393


(70, 140)


F(70, 140) = 1.5*70 + 2.15*140 = $406


to maximize the profit the company should sell 70 small pizzas and 140 big pizzas.