I think its x=27 im not sure sorry if its wrong!
We know that the profit from an item is the sale price minus the cost price. Thus,
1269 - 0.2x² - 830 - 398x
P(x) = -0.2x² - 398x + 439
Local maxima are located at the points where the first derivative of a function are 0
P'(x) = -0.4x - 398
398 = -0.4x
x = -995
There is only one maximum so the average value is -995
I think C but probably try to find something to back it up
All you gotta do is divide the pound by the cost
The correct answer is C and D .
