# Increases and Decrease in Demand

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Increases and Decrease in Demand
Higher demand leads to higher equilibrium price and higher equilibrium quantity supplied Lower demand leads to lower equilibrium price and lower equilibrium quantity supplied

Increases and Decreases in Supply
Higher supply leads to lower equilibrium price and higher equilibrium quantity demanded Lower supply leads to higher equilibrium price and lower equilibrium quantity demanded

Supply and Demand Model Practice
Answer the following on a separate sheet of paper Suppose we are analyzing the market for hot chocolate. Winter starts and the weather turns sharply colder, consumers prefer hot chocolate. The price of cocoa beans, an ingredient in making hot chocolate, decreases. The Surgeon General of the United States announces that hot chocolate causes acne. Protesting farmers stop producing millions of gallons of milk, causing the price of milk, an ingredient in hot chocolate to rise. S D

Activator Chapter 6 Plot the schedule below, which represents the demand for water after a hurricane. 3.00 4.00 5.00 2.00 1.00 Price QD QS \$6 60 5 10 50 4 20 40 3 30 2 1 S 6.00 Price Ceiling D

Price Ceilings Price Ceiling – government imposed, legal maximum price that can be legally charged for a good/service New York introduced rent control in the early 1940s as a way to provide affordable housing Price ceiling causes a shortage in the amount of the product

Input Costs \$7.25 x 40 hours = \$290 \$290 x 4 weeks = \$1160
\$1160 x 5 workers = \$5800 \$5800 x 12 months = \$69,600 \$9.00 x 40 hours = \$360 \$360 x 4 weeks = \$1440 \$1160 x 5 workers = \$7200 \$5800 x 12 months = \$86,400

Activator Chapter 6 Plot the schedule below, which represents the demand for laborers in the market. 4.25 5.25 6.25 2.25 1.25 Price QD QS \$7.25 60 6.25 10 50 5.25 20 40 4.25 30 2.25 1 Price Floor S 7.25 D

Price Floor Price Floor – government imposed, legal minimum price at which a good can be sold Minimum wage is a well-known price floor Minimum wage can cause a surplus of workers

Price ceilings Equilibrium Price ceiling Quantity Price 2 200 800 100
1 April 2017 Price ceilings Equilibrium Price ceiling D Quantity Price 3 2 200 800 4 S 100 D Quantity Price 3 2 200 4 S 100 Price Ceiling Shortage 800

Price Ceilings in Apartments
1 April 2017 Price Ceilings in Apartments

Price controls: price floors
1 April 2017 Price controls: price floors Equilibrium Price floor D Quantity of icecreams Price 3 2 200 4 S 100 D Quantity of icecreams Price 3 2 200 600 4 S 100 Surplus Price Floor 600

1 April 2017

Minimum Wage Videos Stossel 2012 (dvd)

Application – Price Ceiling
Price of Ice Cream Cones Scenario: the government places a price ceiling on ice cream cones as a result of complaints and lobbying from the Ice-Cream Eaters of America. The price ceiling is at \$2.00 a cone. Graph the following schedule based on the price points and qs/qd. Supply Demand Equilibrium point \$3 Price ceiling 2 Shortage of 50 cones Price of Ice Cream Cones Quantity Demanded Quantity Supplied \$3 100 2 125 75 Quantity supplied Quantity demanded Quantity of Ice-Cream Cones 125 The government imposes a price ceiling of \$2. Because the price ceiling is below the equilibrium price of \$3, the market price equals \$2. At this price, 125 cones are demanded and only 75 are supplied, so there is a shortage of 50 cones.

Application – Price Floor
Price of Ice Cream Cones Surplus of 40 ce Cream Cones Scenario: the government places a price floor on ice cream cones as a result of complaints and lobbying from the National Organization of Ice-Cream Makers. The price floor is at \$4.00 a cone. Graph the following schedule based on the price points and qs/qd. Supply Demand Price floor \$4 3 Equilibrium point Price of Ice Cream Cones Quantity Demanded Quantity Supplied \$4 80 120 3 100 Quantity supplied Quantity demanded Quantity of Ice-Cream Cones 120 The government imposes a price floor of \$4, which is above the equilibrium price of \$3. Therefore, the market price equals \$4. Because 120 cones are supplied at this price and only 80 are demanded, there is a surplus of 40 cones.

A store sells cheddar cheese by the pound

Teacher Pay and Price Ceilings

Non-Binding Price Ceiling
Non- Binding Price Ceiling – price ceiling is above equilibrium and thus has no effect on the equilibrium

Non-Binding Price Floor
Non- Binding Price Floor – price floor is below equilibrium and thus has no effect on the equilibrium

Activator – Chapter 5 Elasticity and its Application
List an item that you would buy less of if the price increased List an item that you would buy more of if the price decreased List an item that you would continue to buy, even if the increased

Elasticity Elasticity – measure of the responsiveness of quantity demanded or quantity supplied to a change in price Price elasticity of demand – measures how consumers will cut back or increase their quantity demanded for a product when prices rise or fall Measures the extent to which changes in price causes changes in quantity demanded. Helps determine how much a price change will influence the qd of any given product

Elastic Demand Elastic – quantity demanded changes drastically when a price rises or falls A consumer is very responsive to price changes

Inelastic Demand Inelastic - changes in price cause a relatively small change in quantity demanded Consumers continue to purchase regardless of a price change

Slope of the Curve P P P2 P2 P1 P1 D D QD QD

Elastic Demand Curve P 80,000 40,000 10,000 D 10 QD 100

Inelastic Demand Curve
P \$3.00 1.50 .50 D QD

Determinants of Demand Elasticity
Availability of Close Substitutes Pepsi/Coke, Butter/Margarine Necessities versus Luxuries Medicine versus a luxury automobile 3. Definition of the Market Food – broad category (inelastic) Ice Cream – narrower (more elastic) Vanilla Ice Cream – very narrow category (very elastic) 4. Time Horizon Longer time horizon – more elastic Gas in the short run is inelastic, but over time elastic

Elastic Supply Elastic – suppliers can easily increase or decrease their quantity supplied in the short run

Inelastic Supply Inelastic – suppliers have difficulty changing the quantity supplied

Elastic Supply Curve P S 10 1 5 20 QS

Inelastic Supply Curve
\$3.00 1.50 .50 D QD

Elasticity of Supply S D3 D2 D1 Price per painting P3 P2 P1 1
Quantity of paintings

Elasticity of Supply S D3 D2 D1 Price per ticket \$1000 \$500 \$100
Quantity of seats 80,000

Computing the Price Elasticity of Demand
Price elasticity of demand = Percentage change in quantity demanded Percentage change in price Value is less than 1, it is considered inelastic. Inelastic – Demand is < 1 Value is greater than one, demand is elastic. Elastic – Demand is > than 1 Value is equal to one, demand is unitary elastic. Unitary Elastic – Demand is = 1 Value is equal to 0, demand is perfectly inelastic. Perfectly Inelastic – Demand is = 0 Value is equal to infinity, demand is perfectly elastic Perfectly Elastic – Demand is = infinity

Computing the Price Elasticity of Demand
Price elasticity of demand = Percentage change in quantity demanded Percentage change in price Percentage Change in QD – 25% Percentage Change in Price – 15% Percentage Change in QD – 10% Percentage Change in QD – 15% .25_ .15 = 1.67 Elastic .10_ .15 = .67 Inelastic .15_ .15 = 1 Unitary Elastic

Application – Elasticity of Ice Cream Cones The Midpoint Method
(Q2 – Q1) / [(Q2+Q1) / 2] (P2 – P1) / [(P2 + P1) / 2] Price Elasticity = Price 3.00 5.00 6.00 \$7.00 2.00 1.00 Quantity Demanded of Ice-Cream Cones per week (Q2 – Q1) / [(Q2+Q1) / 2] _10___ 15 = .67 Horizontal is more elastic “E” \$1___ \$3.5 = .29 (P2 – P1) / [(P2 + P1) / 2] = 2.3 .67_ .29 % change in qd % change in price 4.00 Elastic

The Midpoint Method (Q2 – Q1) / [(Q2+Q1) / 2] (P2 – P1) / [(P2 + P1) / 2] Price Elasticity = Price 8.00 \$10.00 8 10 Quantity A 10 – 8_ 9 = .22 \$10 – 8_ \$9 = .22 B A B 22% = 1 Unitary Elastic A B 10 – 8__ 9 = .22 \$10 – 8 9 = .22 .22 = 1 Unitary Elastic

Application – Elasticity of Table Salt
(Q2 – Q1) / [(Q2+Q1) / 2] (P2 – P1) / [(P2 + P1) / 2] Price Elasticity = Price 3.00 5.00 6.00 \$7.00 2.00 1.00 Quantity Demanded of Table Salt 5 ___ 12.5 = .40 (Q2 – Q1) / [(Q2+Q1) / 2] Vertical is more elastic “I” \$4___ \$4 = 1 (P2 – P1) / [(P2 + P1) / 2] = .4 % change in qd % change in price 4.00 Inelastic

Elasticity Application 1
(Q2 – Q1) / [(Q2+Q1) / 2] (P2 – P1) / [(P2 + P1) / 2] Use the formula to show how you determine elasticity of demand for the graph. Q2 _______ - Q1_______ = ______ / Q2 ______+ Q1 _______ / 2 = _______ = ________ P2 _______ - P1_______ = ______ / P2 ______+ P1 _______ / 2 = _______ = ________ - Elasticity QD______ /______P = ________ Did the price change cause an elastic or inelastic response in the QD for ice cream cones? ________________________________________________ .67 20 10 10 20 10 15 5 3 2 5 3 4 .50 1.34 Elastic

Elasticity Application 2
(Q2 – Q1) / [(Q2+Q1) / 2] (P2 – P1) / [(P2 + P1) / 2] Use the formula to show how you determine elasticity of demand for the graph. Q2 _______ - Q1_______ = ______ / Q2 ______+ Q1 _______ / 2 = _______ = ________ P2 _______ - P1_______ = ______ / P2 ______+ P1 _______ / 2 = _______ = ________ - Elasticity QD______ /______P = ________ Did the price change cause an elastic or inelastic response in the QD for insulin? ________________________________________________ Inelastic

Price of a slice of pizza
Total Revenue Total Revenue – the total amount paid by buyers and received by sellers of a good; total amount of money generated by the firm through sales Price of the goods x quantity demanded = Total Revenue Price of a slice of pizza Quantity Demanded Per day Total Revenue \$.50 300 150 \$1.00 250 \$1.50 200 \$2.00 135 270 \$2.50 100 \$3.00 50

Elasticity Application 3
Scenario: The Apple store in St. John’s Mall made the decision to drop the price of their Ipod Nano from \$150 to \$125. As a result, the sale of Nano’s increased from 200 a week to Create a Demand Schedule and Curve based on the above information. Price Per Ipod Nano Price of Nanos QD per week 150 125 150 125 200 250 QD Use the formula to show how you determine elasticity of demand for the graph. Q2 _______ - Q1_______ = ______ / Q2 ______+ Q1 _______ / 2 = _______ = ________ P2 _______ - P1_______ = ______ / P2 ______+ P1 _______ / 2 = _______ = ________ - Elasticity QD______ P______P = ________ Did the price change cause an elastic or inelastic response in the QD for Nanos? ________________________________________________ Elastic Elastic 2. Did the price change cause an elastic or inelastic response in the QD for Nano’s? ___________________ 3. If the firm drops their price by _________%, they will see an increase in sales of __________% 4. To determine if this is a good decision for the firm, calculate the total revenue of each price: - Multiply the first price of the Nano by the first QD – \$______ x _______ = ___________________ - Multiply the second price of the Nano by the second QD – \$ ______ x _______ = __________________ 5. Which price point generates the most total revenue? ______________________ \$30,000 \$31250 125

.18 What is the price elasticity of demand when the price changes from \$1 to \$2? _________ *Use the midpoint method formula to determine the answer to #1* Q2 – Q1__ ________ (Q2 + Q1)/ = ________________ = ___________ P2 – P1__ ________ (P2 + P1)/2 20 170 .12 1 .67 1.5 Based on the above result, demand for Moonbucks coffee at this price range is (elastic/unit elastic/inelastic)

1.22 What is the price elasticity of demand when the price changes from \$5 to \$6? _________ *Use the midpoint method formula to determine the answer to #1* Q2 – Q1__ ________ (Q2 + Q1)/ = ________________ = ___________ P2 – P1__ ________ (P2 + P1)/2 20 90 .22 1 .18 5.5 Based on the above result, demand for Moonbucks coffee at this price range is (elastic/unit elastic/inelastic)

The Flaw in Point Elasticity of Demand Percentage Change from the Original
Elasticity = Percentage change in Quantity Demanded/Percentage change in Price % Q % P Price 8.00 \$10.00 8 10 Quantity A 10 – 8 X 100 10 = .20 \$8 – 10 X100 \$8 = -.25 B A B .20_ -.25 = -.8 Inelastic A B 8 – X 100 8 = -.25 \$10 – 8 X100 \$10 = .20 -.25_ .20 = -1.25 Elastic

Due Wednesday Determinants of Supply Video Supply and Demand Practice
Supply and Demand Application Supply and Demand Review Tennis Ball Simulation SQ3R Prices & Supply and Demand Crossword Puzzle Study Guide Terms Essential Questions Standards Sheet & Test Corrections Notes Daily Tens

Due Wednesday Demand Curve Assignment Chapter 4 Application Worksheet
Supply and Demand Model Practice Video supply and demand chart Supply and demand review Supply and Demand Application Elasticity of demand Daily tens Notes (4-6) Terms