
William W. answered 06/10/23
Experienced Tutor and Retired Engineer
Write the profit function. Let P(x) be the profit where "x" is the number of bottles produced/sold:
For the first 11000 bottles the profit is: 11000(4)
Beyond the first 11,000 the number of bottles sold is (x - 11000) and the profit per bottle is [4 - 0.0003(x - 11000)].
So P(x) = 11000(4) + (x - 11000)[4 - 0.0003(x - 11000)].
P(x) = 44000 + (x - 11000)(4 - 0.0003x + 3.3)
P(x) = 44000 + (x - 11000)(7.3 - 0.0003x)
P(x) = 44000 + 7.3x - 0.0003x2 - 80300 + 3.3x
P(x) = - 0.0003x2 + 10.6x - 36300
To maximize, take the derivative and set it equal to zero. This is a negative quadratic so it will have a max value (which is what we are being asked for).
P'(x) = -0.0006x + 10.6
-0.0006x + 10.6 = 0
0.0006x = 10.6
x = 17667 bottles
The profit when 17667 bottles are sold is P(17667) = - 0.0003(17667)2 + 10.6(17667) - 36300 = $57,333.33