Conceptual Understanding
Marginal Revenue
Maximize Profit
100

At what quantity of donuts is the profit of the donut shop maximized?

When marginal profit=0, when mr=mc.

100

If a company sells donuts at 5 dollars per donut, what is the marginal revenue from one donut?

5 dollars

100

The price per unit is given as P(x)=2000-x and the cost function is given as C(x)=100+4x, what price should be charged to maximize profit?


R(x)=x(2000-x)

The profit function is R(x)-C(x)

= 2000x-x2-(100+4x)=2000x-x2-100-4x

=1996x-x2-100

Therefore, the marginal profit function is:

Mp(x)=1996-2x

x=998

P(x)=2000-x=2000-998

P=1002

200

Why is there an inverse relationship between price and quantity demanded?

Because of the income and substitution effects. (We CAN buy more and the trade-off between donuts and other goods decreases.)

200

If the profit and cost functions of a company are

P(x)=3x2-6x+7

C(x)=-3x2+9x-7

What is the marginal revenue function?

R(x)=P(x)+C(x)

R(x)=3x

R'(x)=3

The marginal revenue is 3 dollars per unit.

200

A company has a revenue function of

R=25x2

as well as a cost function of 

C=2x3-50x2+60x+2

At what quantity is the profit maximized?

At x=5.