A manufacturer of a certain brand of appliance estimates that he can sell 5000 units a year at Php 900.00 each and that he can sell 1500 units more per year for each Php 100.00 decrease in price? What price per unit will give the greatest returns?

First solve the return in each price per unit

Return = number units sold x price per unit

Return1 = 5000 units x Php 900

Return1 = php 4,500,000

Next is solve the other price per unit

Return2 = number units sold x price per unit

Return2 = (5000 + 1500 units0 x (php 900 - 100)

Return2 = php 5,200,000

So the php 800 per unit will have greater return