Question

When priced at 300 pesos each, a toy has an annual sales of 4000 units. The manufacturer estimates that each 10 pesos increase per unit will decrease the sales by 100 units. Find the unit price that will maximize the total revenue.

Answer 1

sales=4000-100((p-300)/10 where p is the price.

sales=4000-10p+3000

revenue=sales*p= p(7000-10p) so revenue has zeroes at p=0 and p=700, so a max occurs at p=350

check all my math, I did it in my head.