Question: [Requires calculus] In the above problem show that 40 units is not the profitmaximizing output and compute profit there. Then find the profit-maximizing output and calculate profit.
a. Find the percentage differences between actual and maximum profits, and actual and profit-maximizing levels of output. Are you surprised that profit is close to its maximum value for so large a range of outputs?
b. What might the above problem suggest about using rules of thumb, that is, relatively rough estimates, as opposed to exact calculations?