<< Chapter < Page Chapter >> Page >

Whatever the firm’s quantity of production, total revenue must exceed total costs if it is to earn a profit. As explored in the chapter Choice in a World of Scarcity , fixed costs are often sunk costs    that cannot be recouped. In thinking about what to do next, sunk costs should typically be ignored, since this spending has already been made and cannot be changed. However, variable costs can be changed, so they convey information about the firm’s ability to cut costs in the present and the extent to which costs will increase if production rises.

Why are total cost and average cost not on the same graph?

Total cost, fixed cost, and variable cost each reflect different aspects of the cost of production over the entire quantity of output being produced. These costs are measured in dollars. In contrast, marginal cost, average cost, and average variable cost are costs per unit. In the previous example, they are measured as cost per haircut. Thus, it would not make sense to put all of these numbers on the same graph, since they are measured in different units ($ versus $ per unit of output).

It would be as if the vertical axis measured two different things. In addition, as a practical matter, if they were on the same graph, the lines for marginal cost, average cost, and average variable cost would appear almost flat against the horizontal axis, compared to the values for total cost, fixed cost, and variable cost. Using the figures from the previous example, the total cost of producing 40 haircuts is $320. But the average cost is $320/40, or $8. If you graphed both total and average cost on the same axes, the average cost would hardly show.

Average cost tells a firm whether it can earn profits given the current price in the market. If we divide profit by the quantity of output produced we get average profit    , also known as the firm’s profit margin . Expanding the equation for profit gives:

average profit = profit quantity produced = total revenue – total cost quantity produced = total revenue quantity produced total cost quantity produced = average revenue – average cost

But note that:

average revenue = price × quantity produced quantity produced = price

Thus:

average profit = price – average cost

This is the firm’s profit margin . This definition implies that if the market price is above average cost, average profit, and thus total profit, will be positive; if price is below average cost, then profits will be negative.

The marginal cost of producing an additional unit can be compared with the marginal revenue gained by selling that additional unit to reveal whether the additional unit is adding to total profit—or not. Thus, marginal cost helps producers understand how profits would be affected by increasing or decreasing production.

A variety of cost patterns

The pattern of costs varies among industries and even among firms in the same industry. Some businesses have high fixed costs, but low marginal costs. Consider, for example, an Internet company that provides medical advice to customers. Such a company might be paid by consumers directly, or perhaps hospitals or healthcare practices might subscribe on behalf of their patients. Setting up the website, collecting the information, writing the content, and buying or leasing the computer space to handle the web traffic are all fixed costs that must be undertaken before the site can work. However, when the website is up and running, it can provide a high quantity of service with relatively low variable costs, like the cost of monitoring the system and updating the information. In this case, the total cost curve might start at a high level, because of the high fixed costs, but then might appear close to flat, up to a large quantity of output, reflecting the low variable costs of operation. If the website is popular, however, a large rise in the number of visitors will overwhelm the website, and increasing output further could require a purchase of additional computer space.

For other firms, fixed costs may be relatively low. For example, consider firms that rake leaves in the fall or shovel snow off sidewalks and driveways in the winter. For fixed costs, such firms may need little more than a car to transport workers to homes of customers and some rakes and shovels. Still other firms may find that diminishing marginal returns set in quite sharply. If a manufacturing plant tried to run 24 hours a day, seven days a week, little time remains for routine maintenance of the equipment, and marginal costs can increase dramatically as the firm struggles to repair and replace overworked equipment.

Every firm can gain insight into its task of earning profits by dividing its total costs into fixed and variable costs, and then using these calculations as a basis for average total cost, average variable cost, and marginal cost. However, making a final decision about the profit-maximizing quantity to produce and the price to charge will require combining these perspectives on cost with an analysis of sales and revenue, which in turn requires looking at the market structure in which the firm finds itself. Before we turn to the analysis of market structure in other chapters, we will analyze the firm’s cost structure from a long-run perspective.

Key concepts and summary

In a short-run perspective, a firm’s total costs can be divided into fixed costs, which a firm must incur before producing any output, and variable costs, which the firm incurs in the act of producing. Fixed costs are sunk costs; that is, because they are in the past and cannot be altered, they should play no role in economic decisions about future production or pricing. Variable costs typically show diminishing marginal returns, so that the marginal cost of producing higher levels of output rises.

Marginal cost is calculated by taking the change in total cost (or the change in variable cost, which will be the same thing) and dividing it by the change in output, for each possible change in output. Marginal costs are typically rising. A firm can compare marginal cost to the additional revenue it gains from selling another unit to find out whether its marginal unit is adding to profit.

Average total cost is calculated by taking total cost and dividing by total output at each different level of output. Average costs are typically U-shaped on a graph. If a firm’s average cost of production is lower than the market price, a firm will be earning profits.

Average variable cost is calculated by taking variable cost and dividing by the total output at each level of output. Average variable costs are typically U-shaped. If a firm’s average variable cost of production is lower than the market price, then the firm would be earning profits if fixed costs are left out of the picture.

Problems

Return to [link] . What is the marginal gain in output from increasing the number of barbers from 4 to 5 and from 5 to 6? Does it continue the pattern of diminishing marginal returns?

Got questions? Get instant answers now!

Compute the average total cost, average variable cost, and marginal cost of producing 60 and 72 haircuts. Draw the graph of the three curves between 60 and 72 haircuts.

Got questions? Get instant answers now!

Questions & Answers

With the aid of diagrams,compare the short run equilibrium positions of a perfect competitor and an imperfect competitors
Monlay Reply
What is the term consultation in economics?
Nthabiseng Reply
why is it that the long run Average cost curve does not touch that of the short run curve at its minimum?
Baah Reply
In few words, what is the role of interest rate in economy?
Carlos Reply
what is population
Nyakeh Reply
total number of people in a given area or country
Clement
the total number of people at a given area or country
Clement
total number of people in a given area or country
okhiria
What is price Elasticity of demand?.
Samuel
The responsiveness of the quantity of a commodity demanded to a change in its price, expressed as the percentage change in quantity demanded divided by the percentage change in price.
EMMANUEL
why is it that the long run Average cost doesn't touch the short run cost curve at its minimum?
Baah
what is supply
Precious
please rice and beans will be what type of demand but note we mostly cook it together
Oladosu Reply
complementary or joint demand
Yillah
but did you know you can demand for rice without beans so how is it joint or complementary
Oladosu
From my point of view, rice and beans are replaceable goods, hence they can't be complementary.
Carlos
what are the money value
Wisdom Reply
Nothing more than a purchase power, in other words, $100 now, must have the same value after 1 year.
Carlos
what is Monopoly
Rebecca Reply
what is money
Lawal Reply
It can be define as a big transaction that can control any business for one place to another base.
Akinlo
money is recognisable note to accept both parties selling and buying
Hassan
i don still understan
Rene
hey
Abdul
hi
Rene
money is anything generally accepted as a medium of exchange
Awwal
Money is anything generally accepted as a medium of exchange and for the settlement of goods and services .
Korda
hi good ppl, pls help out
Tumi
discuss human and natural resources as develop strategies ro improving living condition of citizens in developing countries.
Tumi
I don't understand the question.
Naomi
it's a form of currency used for 2 or more individuals or parties in order to reach their amicable personal or business attainment. one must understand that money itself can manifest in multiple fashions for which the individuals or parties adheres.
are u trying to say we shld discuss ways in which human natural resources help in improving living condition of citizens in developing countries?
Naomi
money is a legal thunder generally accepted as a medium of exchange for the payment of debt ,goods and services
Naomi
money is a way of payment.
Carlos
money is any thing that is generally accepted as a medium of exchange good for good and settlement of debt and means of payment
Yillah
money is nothing but a object which is used for exchange of goods and services.
Harshita
money is anything that is generally accepted as payment of goods and services and settlement of debt
Rebecca
what is demand
Melissa Reply
demand is where the customer is willing and able to buy goods and services during a given period of time
idk
demand is the ability and willingness of an individual to buy goods and services at a given price in a particular period of time
Alpha
demand is the ability to buy a specific quantities of goods and services at a given price and at a specific period of time
rosemary
what are the rules of demand
rosemary
Rosemary Nsebon, Do you mean laws of demand?
Alpha
what are the rules of demand
Rene
the rule of demand is the higher the price the lower the quantity demanded and the lower the price the higher the quantity demanded
mbi
thank
Rene
what is unemployment
Rebecca
unemployment is a scenario or a phenomenon in an economy whereby people are willing are able to work but cannot a job
mbi
Suppose you have a team of two workers: one is a baker and one is a chef. Explain why the kitchen can produce more meals in a given period of time if each worker specializes in what they do best than if each worker tries to do everything from appetizer to dessert. please I need a urgent answer
Oladosu Reply
Enables individuals and countries to consume a variety of goods and services
Iddrisu
what is the meaning of competency
Oladosu Reply
competency is an ability and courage to do something perfectly
Abdullahi
ability to perform some task
Segun
rival
Ray
thanks 🙏 it is also the same with the core competency
Oladosu
A sufficient supply
Ebenezer
Ebenezer you mean the (core competency) right?
Oladosu
what is mean,median and mode
Ikeh Reply
mean is the average number of a given data
Gallant
median is the middle number of a given data
Gallant
in a given data sorry
Mitchel
hi
Sajib
Pls am new here
Physcal
what are development bank in Nigeria
Adedigba Reply
.hi
Physcal
hi
Adedigba
hw
Physcal
and cool
Rosie
nice to meet everyone
Rosie
hi how are dears
Mumtaz
how can we development economic in our country
Mumtaz
hi
Charm
Payroll and​ 4p
Wasuroj
Agriculture
Wasuroj
Export
Wasuroj
Transport
Wasuroj
Change management​ and​ cerrancy
Wasuroj
Empoyee
Wasuroj
Lawyer army and​ Lawyer​
Wasuroj
animal husbandry essay
Rakuane Reply
what's the primary location of capital and money market respectively
ALIMI

Get the best Principles of economics course in your pocket!





Source:  OpenStax, Principles of economics. OpenStax CNX. Sep 19, 2014 Download for free at http://legacy.cnx.org/content/col11613/1.11
Google Play and the Google Play logo are trademarks of Google Inc.

Notification Switch

Would you like to follow the 'Principles of economics' conversation and receive update notifications?

Ask