A community bird-watching society makes and sells simple bird feeders to raise money for its conservation activities. The materials for each feeder cost $4, and the society sells an average of $24 per week at a price of $8 each. The society has been considering raising the price, so it conducts a survey and finds that for every dollar increase, it loses 3 sales per week.
(a) Find a function that models weekly profit in terms of price per feeder. (Let x represent the price per feeder and P represent the profit.)
(b) What price should the society charge for each feeder to maximize profits?
(c) What is the maximum weekly profit?
The number of units sold is dependent on the price
starts at 24 with price 8
as price rises by 1 units goes down by 3
units sold then becomes (24 - 3(x-8) ) = 48 - 3x
PROFIT is number of units sold * price - units sold * cost
(48-3x) * x - (48-3x) * 4 <=====simplify this
-3x^2 + 48x -192 + 12x
a) PROFIT = -3x^2 + 60x - 192
b) Max occurs at - b/2a = -60 / (-3*2) = 10 dollars price
c ) -3(10^2) + 60(10) - 192 = 108 dollars profit