Question

Suppose that market demand is Q = 660 – 12P and marginal cost is MC = 5. The consumer surplus in a perfectly competitive market is $___________, while the consumer surplus in a monopoly market is $ __________.
a. 5,000; 3,750

b. 15,000; 7,500

c. 15,000; 3,750

d. 0; 7,500

Answer 1

Answer: 15000; 3750

Explanation:

From the question,

Q = 660 – 12P

MC = 5

The consumer surplus in a perfectly competitive market will be:

P = MC

Therefore, P = 5

Q = 660 - 12P = 660 - 12(5) = 660 - 60 = 600

Consumer surplus = 1/2 × (55 - 5) (600)

= 1/2 × 50 × 600

= 15,000

For monopoly, MR = MC

Total Revenue = P × Q

Since Q= 660 - 12P

P = (660 - Q)/12

TR = P × Q

= (660 - Q)/12 × Q

= (660Q- Q²)/12 × Q

MR = (660 - 2Q)/12

MR = MC

(660 - 2Q)/12 = 5

(660 - 2Q) = 5 × 12

660 - 2Q = 60

2Q = 660 - 60

2Q = 600

Q = 600/2

Q= 300

Since P =(660 - Q)/12

= (660 - 300)/12

= 360/12

= 30

Consumer surplus = 1/2 × (55 - 30) (30)

= 1/2 × 25 × 300

= 3750

Therefore, the answer is 15000; 3750