SHS

Applied Economics
Week 4: Module 4
ABM/GAS - Applied Economics
Grade 11/12: Week 4: Module 4
First Edition, 2020

Copyright © 2020
La Union Schools Division
Region I

All rights reserved. No part of this module may be reproduced in any form
without written permission from the copyright owners.

Development Team of the Module

Author: Arnel A. Barroga, T-III

Editor: SDO La Union, Learning Resource Quality Assurance Team

Illustrator: Ernesto F. Ramos Jr., P II

Management Team:

ATTY. Donato D. Balderas, Jr.

Schools Division Superintendent

Vivian Luz S. Pagatpatan, PhD

Assistant Schools Division Superintendent

German E. Flora, PhD, CID Chief

Virgilio C. Boado, PhD, EPS in Charge of LRMS

Lorna O. Gaspar, EPS in Charge of Applied Economics

Michael Jason D. Morales, PDO II

Claire P. Toluyen, Librarian II
Applied Economics
Week 4: Module 4
 Target

To the casual observer, market activity seems to be a bewildering and

uncoordinated mass of transactions. Each individual in the market society is free
to buy what and when he pleases, to sell what and when he pleases, to produce or
to consume what he pleases, or to refrain altogether from any or all of these
activities. Transactions may involve any of innumerable commodities or services,
they may involve any of a wide range of quantities and qualities, and they may be
concluded at any of a wide variety of prices.

Market pricing is a means of organizing economic activity. It does this

primarily by coordinating the decisions of consumers, producers, and owners of
productive resources. Millions of economic agents who have no direct
communication with each other are led by the price system to supply each other’s
wants. In a modern economy the price system enables a consumer to buy a
product he has never previously purchased, produced by a firm of whose existence
he is unaware, which is operating with funds partially obtained from his own
savings.

Last module, we talked about the market demand, market supply and
market equilibrium. In our new topic, we will link more of these variables to the
market price system.

This learning material will help you to determine the implications of market
pricing on economic decision-making.

After going through this module, you are expected to:

Determine the implications of market pricing on economic decision-making.
ABM_AE12-Ie-h-6

Subtask:
Directions: Give the meaning of the following words/phrases. You may use the
internet to substantiate your ideas.
Price Elasticity__________________________________________________________
Price Elasticity of Demand_______________________________________________
Price Elasticity of Supply________________________________________________

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 Jumpstart

Prices are an expression of the consensus on the values of different things,

and every society that permits exchanges between people has prices. Because
prices are expressed in terms of a widely acceptable commodity, they permit a
ready comparison of the comparative values of various commodities—if shoes are
P300.00 per pair and ball pens are P10.00 each, a pair of shoes is worth 30 ball
pens. The price of anything is its value in exchange for a commodity of wide
acceptability: the price of a car may be some 100 pieces of gold bars or 2500 pieces
of paper currency. Thus, the system of prices can be arranged to reward or penalize
any kind of activity.

Activity 1: Looking back to your lessons

Direction: As we go further, let us try to recall the concepts of market demand,

market supply and market equilibrium. Please answer the following in a clean one-
fourth sheet of paper and attach your answers to this module. Write TRUE if the
statement is correct and FALSE if it is incorrect.

_______ 1. The equilibrium point is the level where the demand and supply curves
intersect.
_______ 2. If the price is above the equilibrium level, the quantity demanded is
greater than the quantity supplied.
_______ 3. If the price is below the equilibrium point, the quantity demanded is
lesser than the quantity supplied.
________4. The law of demand applies during online sales of computers when
consumers rush to buy products at 30% discounts.
_______ 5. The law of supply applies when the producers supply more masks at a
higher price; selling at higher quantity at a higher price increases revenue.
________6. If the price is below the equilibrium level, then the quantity demanded
will exceed the quantity supplied.
________7. Shortage will exist if the price is below the equilibrium point
________8. The law of supply and demand explains the interaction between the
sellers of a product and the buyers.
________9. The demand curve is always downward sloping due to the law of
diminishing marginal utility.
_______10. The supply curve shows an upward slope.

5
 Discover

The Marketing Price System

Directions: Please read this article on Demand, Supply and Elasticity of Clean
Water in the Philippines. This will help you understand better our new lesson.

Demand, Supply and Elasticity of Clean Water in the Philippines

8/27/2015

According to an article created by Vice

News, there are 55 people who die in the
Philippines every day because of the lack
of clean water. As one can see clean water
is greatly needed by all people. As a
student who is lucky to be given all the
necessities needed in life it would be
normal not to think of this because we
normally do not notice it. However, we
need to. According to Katrina Arianne
Ebora, who works for UNICEF’s Water,
Sanitation and Hygiene program in the
Philippines stated that “Over 30 million people in the Philippines do not have
access to improved sanitation facilities.” Also, according to the PIS by 2050 the
population of the areas with poverty in Manila will reach over 9 million! With the
rising population of the Philippines there will be a problem with the economy of
clean water because there will be too much demand for the supply of water.
(Source: https://redmonteconomics.weebly.com/blog/demand-supply-and-
elasticity-of-clean-water-in-the-philippines)

In the article above, the causes and effects of the water shortage around the
Philippines could be best explained if we could understand the concepts of demand
and supply elasticity of the clean water.

A shortage is when there is an excess demand for the quantity supplied.

While surplus is excess in supply. For example, if there are 10 bottles of water and
there are 20 students who want drinking these, then there will be only 10 students
whose demands are met while the others will not be able to be given anything.
There is shortage in the supply. If producers make too many bottles of water and
consumers cannot buy them, there will be surplus.

Price System in a Market Economy

Let us find out more about the price system. We have learned that demand
is the willingness of the consumers to buy goods and services. In economics, the

6
willingness to buy goods and services should be accompanied by the ability to buy,
also called the “purchasing power”. This is referred to as an effective demand
(source: Investopedia).

EQUILIBRIUM CHARACTERISTICS
Equilibrium is a point of balance or a The supply and demand are balanced in
point of rest. It is also called “market- equilibrium.
clearing price”.
Equilibrium price is the price at which The economic forces are balanced and in
the producer can sell all the units he the absence of external influences, the
wants to produce and the buyer can buy (equilibrium) values of economic
all the units he wants variables will not change.
Quantity demanded and quantities The amount of goods or services sought
supplied are equal. by buyers is equal to the amount of
goods or services produced by sellers.

Price System in a Market Economy: Its Characteristics

The prices of goods that we encounter every day to the things we buy play a
crucial role in determining an efficient distribution of resources in a market
system. The prices will help us to make every day economic decisions about our
needs and desires. They are the indications of the acceptance of a product; the
more popular the product, the higher the price that can be charged. Example is
when a table are for sale in your community today and is assumed that they are
not very important as compared to other products or commodities that we need to
survive especially that our movements are very limited.

Neither the producers nor consumers can impact the prices; consumers can
buy whatever they want; nor can producers make and sell whatever they want.
Prices are decided by interactions between the producers and the consumers.

Price acts as a signal for shortages and surpluses which help firms and
consumers respond to changing market conditions.
 If a good is in shortage – price will tend to rise. Rising prices discourage
demand, and encourage firms to try and increase supply.
 If a good is in surplus – price will tend to fall. Falling price encourage people
to buy, and cause firms to try and cut back on supply.
 Prices help to redistribute resources from goods with little demand to goods
and services

The market price is the point that the supply and demand curves intersect.
(Judge, S. 2020)

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 We explore more how equilibrium happens. Let us analyze the charts below. The
chart shows a surplus – the quantity is greater than demand. When quantity is
greater than demand it causes prices to go down

Figure 1. The Equilibrium Figure 2. The Surplus

Point or the Market Price Point
Point

Prices are market driven - The producers can

make what they want and consumers are free to
purchase what they want. This means that customers
live in a market economy. When prices are high,
supply increases as many firms join the market
(Judge, S. 2020). Let’s say the units of cellular
phones. The numbers of suppliers have increased
because of high prices of the cellular phones. When
smartphones were new in the market, there were
fewer producers and prices were high. The high prices

attracted the producers to join the market (Judge, Figure 3. Shortage Point
S. 2020).

In shortage, quantity is less than the demand; it causes prices to go up due

to scarcity. Example of which is the shortage in masks and ethyl alcohol in the
market. There is shortage in the supply, thus, price tends to go up or tends to go
higher (Judge, S. 2020).

Law of Supply and Demand

The law of supply and demand explains the interaction between the sellers of
a product and the buyers. It shows the relationship between the availability of a
particular product and the desire (or demand) for that product has on its price.

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The Law of Demand

Demand is the desire of a consumer to

purchase goods or services and willingness to
pay for that product or services at a given price.
If all other factors remain equal, the higher the
price of a good, the fewer people will demand
that good. “the higher the price, the lower the
quantity demanded” and vice versa. The demand
curve is always downward sloping due to the law
of diminishing marginal utility.
Figure 4. Demand Curve

The Law of Supply

The law of supply demonstrates the

quantities that will be sold at a given price. The
higher the price, the higher the quantity supplied
and vice versa. The law of supply says "as the
price of a product increases, companies will
produce more of the product”. When graphing
the supply vs. the price, the slope rises.

Figure 5. Supple Curve

How Do Supply and Demand Create an Equilibrium Price?

Equilibrium price is the price at which a producer can sell all the units he
wants to produce and a buyer can buy all the units he wants. Supply and demand
are balanced, or in equilibrium. The demand curve is downward sloping; this is due
to the law of diminishing marginal utility. The supply curve is a vertical line;
overtime, supply curve slopes upward; the more suppliers that are expected to
charge higher, the more they are more willing to produce and bring products to the
market. In the equilibrium point, the two slopes will intersect. The market price is
sufficient to induce suppliers to bring to market that same quantity of goods that
consumers will be willing to pay for at that price.

Price Elasticity of Demand and Supply

Price elasticity measures the responsiveness of

the quantity demanded or supplied of a good to a
change in its price. Elasticity can be described as: a)
elastic or very responsive and b) unit elastic, or inelastic
or not very responsive.

 Elastic demand or supply curve indicates Figure 6. The equilibrium

that quantity demanded or supplied point
respond to price changes in a greater than
proportional manner.

9
  Inelastic demand or supply curve is one where a given percentage change
in price will cause a smaller percentage change in quantity demanded or
supplied.
 Unitary elasticity means that a given percentage changes in price leads to
an equal percentage change in quantity demanded or supplied.

Categories of Price Elasticity

According to Agarwal, P. (2018) and Judge, S. (2020), there are four categories of
price elasticity are the following:

I. The Price Elasticity of Demand

Price elasticity of demand is the responsiveness of quantity demanded, or how

much quantity demanded changes, given a change in the price of goods or services.

The mathematical value is negative. A negative value indicates an inverse

relationship between price and the quantity demanded. But the negative sign is
ignored (Judge, S. 2020). Price Elasticity of Demand (PED) = % change in
quantity demanded % Change in price

Figure 7. Price Elasticity of Demand

Elastic Demand (PED > 1) - the percentage change in price brings about a
more than proportionate change in quantity demanded. When the percentage
change in quantity demanded is greater than the percentage change in price, and
the coefficient of the elasticity is greater than 1.
Examples are real estate and housing - are many different housing choices. People
may live in a townhouses, condos, apartments, or resorts. The options make easy
for people to not pay more than they demand.

Inelastic Demand (coefficient of the elasticity is less than 1) – is when an

increase in price causes a smaller % fall in demand. When the percentage change
in quantity demanded is less than the percentage change in price, and the
coefficient of the elasticity is less than 1.

An example is gasoline – gasoline has few alternatives; people with cars

consider it as a necessity and they need to buy gasoline. There are weak
substitutes, such as train riding, walking and buses. If the price of gasoline goes
up, demand is very inelastic. Other Examples: Diamonds, air conditioners, iPhone,
Cigarettes

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 Unitary Elastic Demand - When the percentage change in demand is equal
to the percentage change in price, the product is said to have Unitary Elastic
demand. Unitary elastic - PED or the price elasticity of demand is 1.

Perfectly Elastic - a small percentage change in price brings about a

change in quantity demanded from zero to infinity. The PED is =0 any change in
price will not have any effect on the demand of the product and the percentage
change in demand will be equal to zero (0).

Point Elasticity

 The midpoint elasticity is less than 1. (Ed < 1). Price reduction leads to
reduction in the total revenue of the firm.
 The demand curve is linear (straight line), it has a unitary elasticity at the
midpoint. The total revenue is maximum at this point.
 Any point above the midpoint has elasticity greater than 1, (Ed > 1).

The Income Elasticity of Demand (YED)

The income elasticity of demand is the relationship between changes in

quantity demanded for a good and a change in real income. (YED = % change in
quantity demanded/ % change in income)

Normal Goods – are those goods for which the demand rises as consumer
income rises; positive income elasticity of demand so as consumers’ income rises
more is demanded at each price. These goods shift to the right as income rises.
YED is positive as income rises, the proportion spent on cheap goods will reduce as
now they can afford to buy more expensive goods. An example is the demand for
units of air-conditioning increases as the income of the consumer increases and
the demand for electric fan decreases. The normal good here are the units of air-
conditioning while the inferior goods are the electric fans.

Inferior Goods – the demand decreases when consumer income rises;

demand increases when consumer income decreases. It shifts to the left as income
rises. YED is negative as income rises, the proportion spent on cheap goods will
reduce as now they can afford to buy more expensive goods. Examples: the demand
for cheap/generic electronic goods (let say electric fans) will fall as people income
rises and they will switch to expensive branded electronic goods (unit of air-
conditioning).

Cross Price Elasticity of Demand or (XED)

Cross price elasticity of demand is the effect on the change in demand of one
good as a result of a change in price of related to another product. XED = (% of
change in the quantity demanded of good X / % of change in the price of good Y). If
the value of XED is positive, it is a substitute good. If the value of XED is negative,
therefore it is complements good and if the value of XED is zero, the two goods are
unrelated.

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Price Elasticity of Supply (PES)

The measure of the responsiveness of a quantity to a change in price. It is the

percentage change in supply as compared to the percentage change in price of a
commodity. PES = % change in quantity demanded of a good or service supplied /
% change in price). If supply is elastic, producers can increase output without a
rise in cost or a time delay. If supply is inelastic, firms find it hard to change
production in a given time period.

 If Pes > 1 = supply is price elastic

 Pes = 0 = supply is perfectly inelastic
 Pes = infinity = supply is perfectly elastic
 Pes < 1 = supply is price inelastic

Figure 8. Elastic Supply Figure 9. Inelastic Supply

Figure 11. Perfectly Elastic Supply

Figure 10. Perfectly Inelastic
Supply
Determinants of Price Elasticity of Supply

Agarwal, P. (2020) said, price elasticity of supply can be influenced by the

following factors:

1. Marginal Cost- If the cost of producing one more unit keeps rising as output
rises or marginal cost rises rapidly with an increase in output, the rate of
output production will be limited. The Price Elasticity of Supply will be
inelastic – the percentage of quantity supplied changes less than the change
in price. If Marginal Cost rises slowly, supply will be elastic.
2. Time - Over time price elasticity of supply tends to become more elastic. The
producers would increase the quantity supplied by a larger percentage than
an increase in price.
3. Number of Firms - The larger the number of firms, the more likely the
supply is elastic. The firms can jump in to fill in the void in supply.

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 4. Mobility of Factors of Production- If factors of production are movable, the
price elasticity of supply tends to be more elastic. The labor and other inputs
can be brought in from other location to increase the capacity quickly.
5. Capacity - If firms have spare capacity, the price elasticity of supply is
elastic. The firm can increase output without experiencing an increase in
costs, and quickly with a change in price.

To summarize what we’ve learned:

 A demand curve shows the relationship between quantity demanded and

price in a given market on a graph.
 The law of demand states that a higher price typically leads to a lower
quantity demanded.
 A supply curve shows the relationship between quantity supplied and price
on a graph.
 The law of supply says that a higher price typically leads to a higher quantity
supplied.
 The equilibrium price and equilibrium quantity occur where the supply and
demand curves cross.
 The equilibrium occurs where the quantity demanded is equal to the
quantity supplied.
 If the price is below the equilibrium level, then the quantity demanded will
exceed the quantity supplied.
 Excess demand or a shortage will exist. If the price is above the equilibrium
level, then the quantity supplied will exceed the quantity demanded.
 Excess supply or a surplus will exist. In either case, economic pressures will
push the price toward the equilibrium level.

Explore

Enrichment Activity 1: Check your understanding!

Directions: Please read the sentences carefully. Identify the word or phrase that is
appropriate to each item. Copy and answer in a separate sheet of paper.
1. A ________________ shows the relationship between quantity demanded and price
in a given market on a graph.
2. The __________________________ states that, higher the price, the higher the
quantity supplied.
3. __________________means that a given percentage changes in price leads to an
equal percentage change in quantity demanded or supplied.
4. _______________means the effect on the change in demand of one good as a result
of a change in price of related to another product.
5. __________________ those goods for which the demand rises as consumer income
rises.
6. _______________the coefficient of the elasticity is less than 1; when an increase in
price causes a smaller % fall in demand.

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Assessment 1: Elastic or Inelastic?

Directions: Please conduct a survey or observe the market in your vicinity.

This can make you aware of your environments. Give examples of goods considered
as elastic and inelastic. You may work with your parents and siblings. Copy and
answer in a separate sheet of paper.

ELASTIC GOODS INELASTIC GOODS

1 1
2 2
3 3
4 4
5 5
6 6
7 7

Enrichment Activity 2: Graph Analysis

Directions: Please analyze the graph and answer the questions below. Copy and
answer in a separate sheet of paper.

When do you have a When do you have

surplus in the a shortage in the
supply of product? supply of
____________________ product?
____________________ __________________
____________________ __________________
____________________ __________________
_ __________________
_________

Using the chart above, kindly describe the point where there is a

a) Surplus ____________________________________
b) Shortage ___________________________________
c) Equilibrium in price _________________________

Assessment 2: Situational Analysis

Directions: Please read the statements carefully and answer what is being asked
afterwards. Copy and answer on a separate sheet of paper.
1. In the market, the price elasticity for the demand of canned goods sold by
Friendship Grocery Store is the:
__________________________________________________________________________________
__________________________________________________________________________________
_________________________________________________________________________________.

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2. If demand for sacks of rice in Friendship Grocery Store is price elastic, then a
__________________________________________________________________________________
_________________________________________________________________________________.

3. If the cross-price elasticity between soap bar and liquid soap commodities is
1.5 then
____________________________________________________________________________.

4. The price elasticity of demand for a certain good tends to be:

_______________________________________________________________________________.

5. If the price elasticity of supply of cup noodles is 0.60 and the price increase by 3
percent, then the quantity supplied for cup noodles increases by how by? Show
your solution.
__________________________________________________________________________________
__________________________________________________________________________________
__________________________________________________________________________________

Deepen

How do you respond to price elasticity?

Directions: Read and analyze the statements below and answer the questions
following the problem. Write your answer in a separate one whole sheet of
paper. Your answer should be 4-6 sentences.

People have unlimited needs and wants for their personal satisfaction and because
of that the prices of products easily get changed. Everyone is affected with the new
normal in the market. The prices of products have become very expensive since the
outbreak of the pandemic, not only in our locality, but in the whole world.

If your income or the income of your family is not enough to purchase the basic
commodities needed by your family, what goods would you buy, instead? What
economic or marketing strategies would you apply? How would you respond to the
price changes of these commodities? What is your long-term plan for the
sustainability of acquiring your needs and wants as an individual amidst this
pandemic?

15
 Gauge

ANSWER ME, PLEASE?

Directions: Read carefully each item. Use a separate sheet for your answers. Write
only the letter of the best answer for each test item.

1. What do you call the situation where there is an excess supply for the
quantity demanded?
A. Shortage B. Surplus C. Equilibrium D. Breakeven
2. What do you call the situation where there is an excess demanded for the
quantity supplied?
A. Shortage B. Surplus C. Equilibrium D. Breakeven
3. What is referred to as the willingness to buy any goods or services should be
accompanied with the ability to buy?
A. Efficient Demand
B. Effective Demand
C. Quality Demand
D. Equilibrium on Demand
4. When there is equilibrium, the supply and demand are usually?
A. Conflicting B. Unstable C. Balanced D. Matched
5. What is defined as the price at which the producer can sell all the units he
produced in agreement with the buyer?
A. Fixed Price B. Book Value C. Par Price D. Equilibrium Price
6. What acts as a signal for shortage and surpluses?
A. Demand B. Supply C. Price D. Goods
7. Which statement about price is NOT TRUE?
A. Prices are decided by interactions between the buyer and the seller
B. If a good is in a shortage, prices tend to rise
C. If a good is in a surplus, prices tend to fall
D. Price doesn’t really help resources from goods with little demand to goods
or services
8. Which is a situation that causes price to go up due to scarcity when quantity
is less than demand?
A. Shortage B. Equilibrium C. Surplus D. Price Floor
9. Which situation causes price to go down due to oversupply when the
demand is less than the quantity supplied?
A. Price Ceiling B. Surplus C. Shortage D. Equilibrium
10. What shows the interaction of the availability of a product and the desire for
that product on its price?
A. The Theory of Marginal Utility
B. The Law of Demand and Supply
C. The Theory of Marginal Return
D. The Law of Attraction
11. What is called as the desire of a consumer to purchase goods or services at a
given price?

16
 A. Supply B. Equilibrium C. Price Specification D. Demand
12. What measures the responsiveness of the quantity demanded or supplied of
a good to a change in its price?
A. Demand Elasticity
B. Supply Elasticity
C. Price Elasticity
D. Marginal Elasticity
13. What happens when the percentage change in quantity demanded is greater
than the percentage change in price, and the coefficient of the elasticity is
greater than 1?
A. Inelastic Supply
B. Elastic Demand
C. Inelastic Demand
D. Elastic Supply
14. When the percentage change in demand is equal to the percentage change in
price, the product is said to have?
A. Unstable Elastic Demand
B. Stable Elastic Demand
C. Hybrid Elastic Demand
D. Unitary Elastic Demand
15. What is defined as the relationship between changes in quantity demanded
for a good and a change in real income?
A. XED B. YED C. PES D. PED

17
 18
ENRICHMENT 2:
Graph Analysis
1) Quantity supplied is ENRICHMENT ACTIVITY 1:
greater than quantity
demanded CHECK YOUR
UNDERSTANDING
2) Quantity demanded is
greater than quantity 1. Demand Curve
supplied
2. The Law of Supply
3) a) Above the equilibrium
3. Unitary Elasticity
point
4. Cross Price Elasticity of
b) Below the equilibrium
Demand
point
5. Normal Goods
c) The surplus and shortage
points meet or intersect 6. Inelastic Demand
SUBTASK:
ACTIVITY 1:
Price Elasticity –
TRUE or FALSE responsiveness of the market
place to a change in price for
1. TRUE
a product
2. TRUE
Price Elasticity of Demand –
3. FALSE economic measure of the
change in the quantity
4. TRUE demanded o purchased of
5. FALSE product in relation to price
changes
6. TRUE
Price Elasticity of Supply-
7. TRUE measures the responsiveness
to the supply of goods or
8. TRUE
services after
9. TRUE
a change in its market price
10. FALSE (source: investopedia)
KEY ANSWERS:
 19
Gauge:
1. B
2. A
3. B
4. C
Assessment 2:
5. D
1. The ratio of the
6. C
percentage change in
7. D quantity demanded for the
goods to the percentage
8. A change in its price
9. B 2. The fall in the price of
10. B sacks of rice will raise total
revenue of the store
11. D
3. The two goods are
12. C substitutes
13. B 4. The smaller in the short
14. D run than in the long run
15. B 5. 1.8 percent
References
Book:

Rosemary P. Dinio, PhD and George A. Villasis. 2017. Applied Economics. Manila:
Rex Book Store, Inc.
E-Sites:

https://www.youtube.com/watch?v=HHcblIxiAAk;

https://www.youtube.com/watch?v=nOlOf_KEnrw

Websites:

Agarwal, P. (2018) Price Elasticity of Supply. Retrieved on June 04 2020 from

https://www.intelligenteconomist.com/price-elasticity-of-supply

Amadeo, K. (2020) Elastic Demand with Its Formula, Curve, and Examples Retrieved
on June 04 2020 from https://www.thebalance.com/elastic-demand-
definition-formula-curve-examples-3305836
https://www.thebalance.com/inelastic-demand-definition-formula-curve-
examples-3305935

Judge, S. (2020) Characteristics of the Price System in a Market Economy. Retrieved

on June 04 2020 fro https://study.com/academy/lesson/characteristics-of-
the-price-system-in-a-market-economy.html

Pettinger, T. (2019) Role and Function of Price in Economy Retrieved on June 04 2020
from https://www.economicshelp.org/blog/1170/economics/role-and-
function-of-price-in-economy/

https://www.investopedia.com/ask/answers/012915/what-difference-between-
inelasticity-and-elasticitydemand.asp

https://www.sparknotes.com/economics/micro/elasticity/problems

https://www.investopedia.com/terms/l/law-of-supply-demand.asp

https://opentextbc.ca/principlesofeconomics/chapter/3-1-demand-supply-and-
equilibrium-in-marketsfor- goods-and-services/

https://global.oup.com/us/companion.websites/9780199811786/student/chapt2/
multiplech

https://opentextbc.ca/principlesofeconomics/chapter/5-1-price-elasticity-of-demand-
and-priceelasticity-of-supply

http://faculty.fortlewis.edu/walker_d/practice_problems_-_elasticity.htm

https://global.oup.com/uk/orc/busecon/economics/gillespie_econ4e/student/mcqs
/ch05/

https://cdn.mises.org/Market%20Theory%20and%20the%20Price%20System_2.pdf?
fbclid=IwAR3V-Qdz_G-s4XWwBKvWFl_0nzSD3sJPefM_jdfcnfP9O_-
fig8W6u3GBqM

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