CFA的问题

讲师：孙嘉宇

A firm faces a downward sloping demand curve, QD = 500 - 20P. The marginal revenue if the price were decreased from $18.00 to $17.95 is closest to:
A. $11.  
B. $13.  
C. $15.

A
[KEY] 
 
Marginal revenue is the change in total revenue per additional unit produced and
sold. At a price of 18, quantity demanded is equal to 500 - 20(18) = 140, and total revenue is 140
x
18 = $2,520.
At a price of 17.95, quantity demanded is equal to 500 - 20(17.95) = 141, and total revenue is 141
x
17.95 =
$2,530.95. Marginal revenue for the 141st unit is 2,530.95 - 2,520 = $10.95.
 A   Marginal revenue is the change in total revenue per additional unit produced and  sold. At a price of 18, quantity demanded is equal to 500 - 20(18) = 140, and total revenue is 140 x 18 = $2,520. At a price of 17.95, quantity demanded is equal to 500 - 20(17.95) = 141, and total revenue is 141 x 17.95 = $2,530.95. Marginal revenue for the 141st unit is 2,530.95 - 2,520 = $10.95.