it cost you c dollars each to manufacture and distribute backpacks. if the backpacks sell at x dollars each, the number sold is given by

n=(a/x-c)+b(100-x)

where a and b are certain positive constanst. what selling price will bring a maximum profit?

1 answer

Profit as a function of x is

P(x) = n (x - c)
= a - cx + 100 bx - bx^2 - cx

Maximum profit occurs when dP/dx = 0
-2c + 100 b = 2xb
x = -c/b + b/50

Check my work.