8. A rational consumer spends all of her income on two goods: Apple and Banana.
Suppose the last dollar spent on Apple increased her total utility from 60 utils to 68 utils
and the last dollar spent on Banana increased her total utility from 25 utils to 29 utils. If
the price of a unit of Apple is 2 Birr, what is the price of a unit of Banana at equilibrium?
9. Suppose the production function is given by Q(L,K) = L3/4K
1/4 Assuming capital is
fixed, find APL and MPL.
10. Given a short run cost function as TC = 1/3Q3
-2Q2
+60Q+100 , find the minimum
value of AVC and MC.
11. What are the similarities and differences between oligopoly and monopolistically
competitive market structure?
12. A firm operates in a perfectly competitive market. The market price of its product is
4 birr and the total cost function is given by TC= 1/3Q3
-5Q2
+20Q+50, where TC is the
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1 answer
If the price of a unit of Apple is 2 Birr, then the amount of Apple she buys is X (in units), and the amount of Banana she buys is Y/2 (in units).
We know that the last dollar spent on Apple increased her total utility from 60 utils to 68 utils. This means that the marginal utility of the last unit of Apple purchased is 8 utils.
Similarly, the last dollar spent on Banana increased her total utility from 25 utils to 29 utils. This means that the marginal utility of the last unit of Banana purchased is 4 utils.
Since the consumer is maximizing her utility, she will equate the marginal utility per Birr spent on Apple to the marginal utility per Birr spent on Banana. This can be represented as:
MUa/price of Apple = MUb/price of Banana
8/2 = 4/price of Banana
4 = 4/price of Banana
price of Banana = 1 Birr
Therefore, the price of a unit of Banana at equilibrium is 1 Birr.
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Assuming capital is fixed, the production function is Q(L,K) = L^(3/4) * K^(1/4).
The Average Product of Labor (APL) is given by APL = Q/L. Substituting the production function, we have:
APL = (L^(3/4) * K^(1/4)) / L
APL = L^(-1/4) * K^(1/4)
The Marginal Product of Labor (MPL) is given by MPL = ∂Q/∂L. Taking the derivative of the production function with respect to L, we have:
MPL = (3/4) * L^(-1/4) * K^(1/4) * K^(1/4)
MPL = (3/4) * K^(1/4) * L^(-1/4) * L^(3/4)
MPL = (3/4) * K^(1/4) * L^(1/2)
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The total cost function is TC = (1/3)Q^3 -2Q^2 + 60Q + 100.
The Average Variable Cost (AVC) is given by AVC = VC/Q, where VC is the total variable cost. The variable cost is the cost that varies with the level of output.
To find the minimum value of AVC, we need to find the minimum value of VC. This occurs where Marginal Cost (MC) is equal to Average Variable Cost (AVC).
MC = ∂TC/∂Q = Q^2 - 4Q + 60
AVC = VC/Q = (TC - FC)/Q
AVC = (1/3)Q^2 - 2Q + 60
Setting MC = AVC, we have:
Q^2 - 4Q + 60 = (1/3)Q^2 - 2Q + 60
(2/3)Q^2 - 2Q = 0
(2/3)Q(Q - 3) = 0
Q = 0 or Q = 3
Since Q cannot be 0, the minimum value of AVC occurs at Q = 3. Substituting this into the average variable cost equation, we get:
AVC = (1/3)(3)^2 - 2(3) + 60
AVC = 11
Therefore, the minimum value of AVC is 11.
To find the minimum value of MC, we can calculate MC at Q = 3:
MC = (3)^2 - 4(3) + 60
MC = 51
Therefore, the minimum value of MC is 51.
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Oligopoly and monopolistically competitive market structures are both imperfect competition market structures, meaning they deviate from the ideal of perfect competition.
Similarities:
1. Both market structures have a small number of sellers in the market.
2. Entry and exit barriers exist in both market structures, although they may be higher in oligopoly compared to monopolistic competition.
3. In both market structures, firms have some degree of market power and can influence prices.
4. Both market structures involve product differentiation to some extent, although it may be greater in monopolistic competition compared to oligopoly.
Differences:
1. Oligopoly involves a few large firms dominating the market, whereas monopolistic competition has many small firms competing with each other.
2. In oligopoly, firms may engage in strategic behavior and engage in collusion or form cartels. In monopolistic competition, firms compete independently and may engage in non-price competition.
3. Oligopoly tends to have higher concentration ratios, meaning a few firms control a large share of the market, whereas monopolistic competition has lower concentration ratios.
4. In oligopoly, there is a high level of interdependence between firms, as they must take into account the actions and reactions of other firms in the market. In monopolistic competition, firms are relatively independent and do not need to consider the actions of other firms as much.
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In a perfectly competitive market, the market price of the product is determined by the intersection of the market demand and supply curves. In this case, the market price is given as 4 birr.
The total cost function is TC = (1/3)Q^3 - 5Q^2 + 20Q + 50.
To find the profit-maximizing level of output for the firm, we need to find the level of output where Marginal Cost (MC) is equal to the market price.
MC = ∂TC/∂Q = Q^2 - 10Q + 20
4 = Q^2 - 10Q + 20
Q^2 - 10Q + 16 = 0
Using the quadratic formula, we can solve for Q:
Q = (-(-10) ± √((-10)^2 - 4(1)(16)))/(2(1))
Q = (10 ± √(100 - 64))/2
Q = (10 ± √36)/2
Q = (10 ± 6)/2
Q = 8 or Q = 2
Since the firm's output level cannot be negative or zero, the profit-maximizing level of output is Q = 8.
To find the Minimum Cost (MC), we substitute Q = 8 into the total cost function:
TC = (1/3)(8)^3 - 5(8)^2 + 20(8) + 50
MC = 100
Therefore, the minimum value of MC for this firm is 100.