Managerial Economics ECO510 final exam
Q # 7:
Given demand Q = 60 – 2P
Supply = 5P - 10
a) The equilibrium price is where demand equals supply
So 60 – 2P = 5P – 10
7P = 70
P = 10
b) In a perfect competition the market maximizing output is given by MR = MC
We have R = PQ
And C = 16 + Q2 + 2Q
So MR = d/dQ (PQ) = P
And MC = d/dQ (16 + Q2 + 2Q) = 2Q + 2
Now MR = MC
P = 2Q + 2
Q = (P – 2)/2
At P = 10, Q = (10-2)/2 = 4
Therefore the profit maximizing output is Q = 4
c) The total profit is given by
Profit = R – C
= PQ – (16 + Q2 + 2Q)
= (10)(4) – (16 + (4)2 + 2(4))
= 40 – (16 + 16 + 8)
= 40 – 40 = 0
d) Since the maximum profit is zero, the other firms will stay in the market and the outcome will persist in the long run
Q # 8
a) Total Revenue equation
Consider Q1 + Q2 in the price equation. Total revenue equation can be calculated as follows:
Total revenue equation = P x Q
= (100 – Q)Q
= 100Q – Q2
Hence the total revenue equation is 100Q – Q2
b. Output of each firm in competitive market:
According to cournot, equilubrium duopoly market share is 1:2. Output of the firm can be calculated as follows:
Managerial Cost = Price
25 = 100 –Q1 – Q2
25 = 100 – Q1 – Q2 (Q1 = 2Q2 According to cournot equilubrium)
Q1 = 37.5 – 0.5Q2 (solve with cournot equilubrium which is Q1 = 2Q2)
Q1 = 18.75
Q2 = 37.5
Price of each firm in competitive market:
Price of the firm is calculated as:
Price = 100 – Q1 – Q2
= 100 – 18.75 – 37.5
= 43.75
Hence, each firm price is $43.75
c. Output of each firm in the in cartel:
Marginal costs for the firms are 50. Output of the firm is calculated as follows:
Marginal Cost = Price
50 = 100 – Q1 – Q2
50 = 100 – 2Q2 – Q2 (According to cournot equilibrium Q1 = 2Q2)
Q1 = 16.67
Q2 = 33.33
Hence the output of firm 1 is 16.67 and the output of firm 2 is 33.33
Price of the each firm in the cartel:
It is calculated as:
Price = 100 – Q1 – Q2
= 100 – 16.67 – 33.33
Price is calculated to be $50
d. Difference in part b and c:
The total output in the competitive market is more and the price is calculated to be lesser in comparison to the cartel total output and price.