Get started for free
Log In Start studying!
Get started for free Log out
Chapter 5: Problem 5
In each \(D(x)\) is the price, in dollars per unit, that consumers are willingto pay for \(x\) units of an item, and \(S(x)\) is the price, in dollars per unit,that producers are willing to accept for \(x\) units. Find (a) the equilibriumpoint, (b) the consumer surplus at the equilibrium point, and (c) the producersurplus at the equilibrium point. $$D(x)=(x-6)^{2}, \quad S(x)=x^{2}$$
Short Answer
Expert verified
The equilibrium point is (3, 9). Consumer surplus is 40.5. Producer surplus is 13.5.
Step by step solution
01
- Set Demand Equal to Supply
To find the equilibrium point, set the demand function equal to the supply function: \[D(x) = S(x)\] This gives us: \[(x-6)^2 = x^2\]
02
- Solve for x
Solve the equation \[(x-6)^2 = x^2\] by expanding it and simplifying: \[(x-6)^2 = x^2\] \[x^2 - 12x + 36 = x^2\] Subtract \(x^2\) from both sides: \[-12x + 36 = 0\] Solve for \(x\): \[x = 3\]
03
- Find the Equilibrium Price
Plug the value of \(x\) back into either \(D(x)\) or \(S(x)\) to find the equilibrium price: \[P = D(3) = (3-6)^2 = 9\] So the equilibrium price is \(9\) dollars per unit.
04
- Calculate Consumer Surplus
Consumer surplus is the area between the demand curve and the equilibrium price line, up to the equilibrium quantity. First find the maximum price that consumers are willing to pay when \(x = 0\): \[D(0) = (0-6)^2 = 36\] The consumer surplus is the area of a triangle with height \(36 - 9 = 27\) and base \(3\): \[\text{Consumer Surplus} = \frac{1}{2} \times 27 \times 3 = 40.5\]
05
- Calculate Producer Surplus
Producer surplus is the area between the supply curve and the equilibrium price line, up to the equilibrium quantity. First find the minimum price that producers are willing to accept when \(x = 0\): \[S(0) = (0)^2 = 0\] The producer surplus is the area of a triangle with height \(9 - 0 = 9\) and base \(3\): \[\text{Producer Surplus} = \frac{1}{2} \times 9 \times 3 = 13.5\]
Key Concepts
These are the key concepts you need to understand to accurately answer the question.
Consumer Surplus Calculation
Consumer surplus represents the difference between what consumers are willing to pay for a good and what they actually pay at the equilibrium price. This surplus is found in the area below the demand curve but above the equilibrium price line, up to the equilibrium quantity.
In our exercise, the demand function is \(D(x) = (x - 6)^2\).
Here’s how we calculate it step-by-step:
1. Find the maximum price consumers are willing to pay when \(x = 0\):
\(D(0) = (0-6)^2 = 36\).
2. Identify the equilibrium price, \(P = 9\).
3. Determine the height difference: \(36 - 9 = 27\).
4. Calculate the consumer surplus as a triangle's area with base \(3\) (the equilibrium quantity) and height \(27\):
\( \text{Consumer Surplus} = \frac{1}{2} \times 27 \times 3 = 40.5\).
Therefore, the consumer surplus at the equilibrium point is \(40.5\).
Producer Surplus Calculation
Producer surplus is the difference between what producers are willing to accept for a good and what they actually receive at the equilibrium price. This surplus is found in the area above the supply curve but below the equilibrium price line, up to the equilibrium quantity.
In the given exercise, the supply function is \(S(x) = x^2\).
Let’s break down how we calculate this step-by-step:
1. Find the minimum price producers are willing to accept when \(x = 0\):
\(S(0) = (0)^2 = 0\).
2. Identify the equilibrium price, \(P = 9\).
3. Determine the height difference: \(9 - 0 = 9\).
4. Calculate the producer surplus as a triangle's area with base \(3\) (the equilibrium quantity) and height \(9\):
\( \text{Producer Surplus} = \frac{1}{2} \times 9 \times 3 = 13.5\).
Hence, the producer surplus at the equilibrium point is \(13.5\).
Demand and Supply Functions
Demand and supply functions represent the relationship between the price of a good and the quantity demanded or supplied.
The demand function \(D(x) = (x - 6)^2\) shows the price consumers are willing to pay for \(x\) units. As \(x\) increases, this price evolves.
The supply function \(S(x) = x^2\) illustrates the price producers are willing to accept for \(x\) units. The price increases as the quantity \(x\) increases.
Key points:
- The demand curve typically slopes downward as higher quantities often mean lower prices consumers are willing to pay.
- The supply curve usually slopes upward as producers require higher prices to supply larger quantities.
- The intersection of these curves is the equilibrium point, where supply equals demand, determining the equilibrium price and quantity.
Equilibrium Price
The equilibrium price is the price at which the quantity of goods demanded by consumers equals the quantity supplied by producers.
To find the equilibrium price, we set the demand function equal to the supply function and solve for \(x\):\[(x-6)^2 = x^2\].
Solving this equation:
1. Expand and simplify the equation: \(x^2 - 12x + 36 = x^2\).
2. Subtract \(x^2\) from both sides: \(-12x + 36 = 0\).
3. Solve for \(x\): \(x = 3\).
Plugging \(x\) back into either function to find price: \(P = (3-6)^2 = 9\).
Thus, the equilibrium price is \(9\) dollars per unit, and the equilibrium quantity is 3 units.
At this point, the demand and supply match perfectly, balancing the market.
One App. One Place for Learning.
All the tools & learning materials you need for study success - in one app.
Get started for free
Most popular questions from this chapter
Recommended explanations on Math Textbooks
Geometry
Read ExplanationPure Maths
Read ExplanationTheoretical and Mathematical Physics
Read ExplanationCalculus
Read ExplanationLogic and Functions
Read ExplanationStatistics
Read ExplanationWhat do you think about this solution?
We value your feedback to improve our textbook solutions.
Study anywhere. Anytime. Across all devices.
Sign-up for free
This website uses cookies to improve your experience. We'll assume you're ok with this, but you can opt-out if you wish. Accept
Privacy & Cookies Policy
Privacy Overview
This website uses cookies to improve your experience while you navigate through the website. Out of these, the cookies that are categorized as necessary are stored on your browser as they are essential for the working of basic functionalities of the website. We also use third-party cookies that help us analyze and understand how you use this website. These cookies will be stored in your browser only with your consent. You also have the option to opt-out of these cookies. But opting out of some of these cookies may affect your browsing experience.
Always Enabled
Necessary cookies are absolutely essential for the website to function properly. This category only includes cookies that ensures basic functionalities and security features of the website. These cookies do not store any personal information.
Any cookies that may not be particularly necessary for the website to function and is used specifically to collect user personal data via analytics, ads, other embedded contents are termed as non-necessary cookies. It is mandatory to procure user consent prior to running these cookies on your website.