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This means that, along the demand curve between point B and A, if the price changes by 1%, the quantity demanded will change by 0.45%. A change in the price will result in a smaller percentage change in the quantity demanded. For example, a 10% increase in the price will result in only a 4.5% decrease in quantity demanded. A 10% decrease in the price will result in only a 4.5% increase in the quantity demanded. Price elasticities of demand are negative numbers indicating that the demand curve is downward sloping, but are read as absolute values. The following Work It Out feature will walk you through calculating the price elasticity of demand.

Finding the price elasticity of demand

Calculate the price elasticity of demand using the data in [link] for an increase in price from G to H. Has the elasticity increased or decreased?

Step 1. We know that:

Price Elasticity of Demand = % change in quantity % change in price

Step 2. From the Midpoint Formula we know that:

change in quantity = Q 2 Q 1 ( Q 2 + Q 1 )/2  × 100 change in price = P 2 P 1 ( P 2 + P 1 )/2  × 100

Step 3. So we can use the values provided in the figure in each equation:

% change in quantity = 1,600 1,800 ( 1,600 + 1,800 )/2  ×  100 = –200 1,700  ×  100 = –11 . 76 % change in price = 130 120 ( 130 + 120 )/2  ×  100 = 10 125  ×  100 = 8 . 0

Step 4. Then, those values can be used to determine the price elasticity of demand:

Price Elasticity of Demand = % change in quantity % change in price = –11.76 8 = 1.47

Therefore, the elasticity of demand from G to H 1.47. The magnitude of the elasticity has increased (in absolute value) as we moved up along the demand curve    from points A to B. Recall that the elasticity between these two points was 0.45. Demand was inelastic between points A and B and elastic between points G and H. This shows us that price elasticity of demand changes at different points along a straight-line demand curve .

Calculating the price elasticity of supply

Assume that an apartment rents for $650 per month and at that price 10,000 units are rented as shown in [link] . When the price increases to $700 per month, 13,000 units are supplied into the market. By what percentage does apartment supply increase? What is the price sensitivity?

Price elasticity of supply

The graph shows an upward sloping line that represents the supply of apartment rentals.
The price elasticity of supply is calculated as the percentage change in quantity divided by the percentage change in price.

Using the Midpoint Method ,

% change in quantity = 13,000 10,000 ( 13,000 + 10,000 )/2  × 100 = 3,000 11,500  × 100 = 26.1 % change in price = $700 $600 ( $700 + $650 )/2  × 100 = 50 675  × 100 = 7.4 Price Elasticity of Supply = 26.1%   7.4% = 3.53

Again, as with the elasticity of demand, the elasticity of supply is not followed by any units. Elasticity is a ratio of one percentage change to another percentage change—nothing more—and is read as an absolute value. In this case, a 1% rise in price causes an increase in quantity supplied of 3.5%. The greater than one elasticity of supply means that the percentage change in quantity supplied will be greater than a one percent price change. If you're starting to wonder if the concept of slope fits into this calculation, read the following Clear It Up box.

Is the elasticity the slope?

It is a common mistake to confuse the slope of either the supply or demand curve with its elasticity. The slope is the rate of change in units along the curve, or the rise/run (change in y over the change in x). For example, in [link] , each point shown on the demand curve, price drops by $10 and the number of units demanded increases by 200. So the slope is –10/200 along the entire demand curve and does not change. The price elasticity, however, changes along the curve. Elasticity between points A and B was 0.45 and increased to 1.47 between points G and H. Elasticity is the percentage change, which is a different calculation from the slope and has a different meaning.

When we are at the upper end of a demand curve, where price is high and the quantity demanded is low, a small change in the quantity demanded, even in, say, one unit, is pretty big in percentage terms. A change in price of, say, a dollar, is going to be much less important in percentage terms than it would have been at the bottom of the demand curve. Likewise, at the bottom of the demand curve, that one unit change when the quantity demanded is high will be small as a percentage.

So, at one end of the demand curve, where we have a large percentage change in quantity demanded over a small percentage change in price, the elasticity value would be high, or demand would be relatively elastic. Even with the same change in the price and the same change in the quantity demanded, at the other end of the demand curve the quantity is much higher, and the price is much lower, so the percentage change in quantity demanded is smaller and the percentage change in price is much higher. That means at the bottom of the curve we'd have a small numerator over a large denominator, so the elasticity measure would be much lower, or inelastic.

As we move along the demand curve, the values for quantity and price go up or down, depending on which way we are moving, so the percentages for, say, a $1 difference in price or a one unit difference in quantity, will change as well, which means the ratios of those percentages will change.

Key concepts and summary

Price elasticity measures the responsiveness of the quantity demanded or supplied of a good to a change in its price. It is computed as the percentage change in quantity demanded (or supplied) divided by the percentage change in price. Elasticity can be described as elastic (or very responsive), unit elastic, or inelastic (not very responsive). Elastic demand or supply curves indicate that quantity demanded or supplied respond to price changes in a greater than proportional manner. An 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. A unitary elasticity means that a given percentage change in price leads to an equal percentage change in quantity demanded or supplied.

Problems

The equation for a demand curve is P = 48 – 3Q. What is the elasticity in moving from a quantity of 5 to a quantity of 6?

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The equation for a demand curve is P = 2/Q. What is the elasticity of demand as price falls from 5 to 4? What is the elasticity of demand as the price falls from 9 to 8? Would you expect these answers to be the same?

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The equation for a supply curve is 4P = Q. What is the elasticity of supply as price rises from 3 to 4? What is the elasticity of supply as the price rises from 7 to 8? Would you expect these answers to be the same?

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The equation for a supply curve is P = 3Q – 8. What is the elasticity in moving from a price of 4 to a price of 7?

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Questions & Answers

Pls where can I found PRICE CONTROL on this app
Samuel Reply
top left corner
JUDE
A situation in an economy with one producer but many consumers
Kabali Reply
What is the theory of population according to Malthus?
Kabali
What is the Malthusian population theory?
Kabali
The Malthusian theory of population state that, where there are means of substinence like food, human beings have the tendency to procreate (ie.give birth) without restraint (ie. control).
George
he stated that population unchecked grows at a geometric progression ie 1,2,4,8,16 while the means food subsistence grows at arithmetic progression ie 1,2,3,4,5---- he declared that population has the tendency to outstrip the means of subsistence
Fung
What is money?
Kabali
money is any commodity that act as a medium of exchange
Fung
money is medium of exchange which is use in taking goods and giving some of it's worth or money value
Madhu
what is a debit card and a credit card?
Milly
a debit card is a payment card used instead of cash while purchasing
Madhu
a credit card is a payment card issued to users to enable cardholder to pay a merchant for goods and services
Madhu
oky tanx
Milly
good
ABDUL
What is an inferior good.?
Kabali
what is monopoly
Richmond Reply
a market situation when there is only one seller of a product representing whole industry.
how
where one business is the dominant one in that market. It determines the market price as they are price makers. No entry, no competition.
karl
it is a market situation where is a single seller and many buyer hear the seller is the price maker the is no free entering and exit in this market
Fung
A situation in the economy where there is one producer and many consumers
Kabali
A market situation where there is one producer and many consumers.
Kabali
Balance of payments for 2018
Mahlatse Reply
what is monopoly and what is monopolaist
Javid Reply
what is the affect of rise in value of dollar ?
Shabana
monopoly"a single firm or company owns all or nearly all of the market for a given type of product or service "monopoly is a price maker ...barrier of entry ,non availability of close substitute.
Shabana
monopolistic competition or market is a situation where there are few or many firm producing identical but differentiated product .eg difference in advertisement ,packing etc
Shabana
monopolistic competition or market is a situation where there are few or many firm producing identical but differentiated product .eg difference in advertisement ,packing
jay
monopoly is a market situation ...where there is a single seller and large number of buyers deals with commodities having no close substitutes......here the sellers are price makers... there is restrictions in the entry and exit of new firms in this market structure....
lovely
what is money?
Hilary
money is a medium of exchange.....through which...commodities are bought and sold
lovely
money is a medium/means of exchange that generally accepted by law
Prince
What is tranfer earnings
Admire
what is savings income?
Limitles
transfer earning is the minimum income that a factor is willing to accept in an occupation,it is also call the supply price of a factor
Fung
what is envelope curve
Dharam
what is depreciation
Fung
depreciation means decrease in value of a assets due to normal wear or year ,means decrease in value of assets like a machine due to its daily use
ru
Refers to wear and tear of capital machinery
apule
what is meant by currency depreciation?
Shabana
an envelope curve is also call an umbrella curve it is any curve that is enclosed by being tangen t to a series of other curves
Fung
fall in the value of currency vis-a-vis any other currency usually $ due to marker forces is called currency depreciation. it is different from devaluation where in value of currency is deliberately reduced to improve BoT
mohammad
depreciation in its broad sense means loss in the value of fixed capital say a tractor due to i) normal wear and tear ii) normal rate of accidental damage iii) expected absolescence to meet this, Depereciation Reserve Fund is created it is calculated by firms on the basis of their experience.
mohammad
what is green revolution ?discuss the achievement of green revolution in India
Sweety Reply
green revolution is the third revolution of agricultural refers to a set of research and development of technology transfer initiative occuring between 1930s and the late 1960s that increased agricultural is called green revolution
Javid
the green revolution happened because to improve the agricultural sector towards adopting mordern methods and improvement of agricultural equipments
Madhu
what calculation for demand and supply
Amoo Reply
what is nationalisation
Awuni Reply
it is a process of converting private assets into public assets by undertaking the control of government or state authority
ru
yes
Emmanuel
so true
Violet
what are some the things that may lead to nationalisation
Fung
Over exploring of customers by the private individuals Also to make the nationalised organisation social reliable and accessible by all
Richard
feeling of one's is called nationalisation. unity among them self .
Madhu
anything which is widely acceptable as a medium of exchange
Shabana Reply
money ,currency
ru
Hello plz,what is the full mean of tertiary?
al Reply
tertiary also called philoshper
Waseem
tertiary means third..for example primary sector ,secondary and tertiary sector... means three number..
ru
ru 9ice tnk
al
your most welcome.
ru
tnz
al
what is money
Tettey
what is a bank
Walters
a financial institution which holds money for its clients ,which collect deposit and lend money at interest and trades generally in money...
Shabana
what is bankers draft ?kindly explain with example .
Shabana
money "anything which is widely acceptable as a medium of exchange"
Shabana
yes u ryt #shabana
Dar
difference between cost and price
Dar
Shallow definition
Adam
cost"the value of input that is the amount of money which is used to produce a good or service . price"an amount of money which has to b paid to buy something.
Shabana
Tertiary is an adjective(pre position) for stages or levels and refers to "top, final, full term ." ; Advanced.
Anderson
bank draft is a type of cheque which a person buy for to pay someone who is not willing to accept a personal cheque .
ru
tertiary sector is an providing any kind of services.
Madhu
primary sector is 'agriculture', secondary sector is ' industrial sector ,and the tertiary sector is ,' service sector' ,
Dharam
subana are you understand now the meaning of bank draft?
ru
what is golden- diamond paradox
Tammanna
what is occupational structure
Madhu Reply
occupational structure refers to the distribution of occupation on the basis of educational ,socoial ,income level in a society or economy
ru
no that is not a exact meaning
Madhu
than what is exact meaning
Dharam
It refers to also the what is the average income of the person
Madhu
what is deficit
Obiajunwa Reply
deficit = expenses > revenue
Waseem
yeah expenses over revenue results in deficit
Paulina
insufficiency
Anderson
What is What is Equilibrium
Bright Reply
from business point of view it is that point where business revanu are equal to its expenses.
ru
in economy where demand is equal to supply is called equalibrium
ru
Equilibrium in economics is where quantity demanded is equal to quantity supplied
Collins
what are the objectives of devaluation
Oyedun
how the government solve the problem of scarcity
SUNDAY Reply
how government solve the problem of scarcity
SUNDAY
by deciding the output limit for every industry and providing resources to these industries according to output limit .the problem can be solved
ru
and by controlling the activity of production like as a mixed economy this problem can be solved
ru
by proper planning to cater the needs of people, demand & supply process may prove helpful. and by imposing heavy import duty on the product to shift the demand towards available alternative sources.
Abida
changing the methods of production, and tax system
Khushal
In problems of scarcity government should adopt a plan or state budget, form a long term policy , deal with corruption , mobilise resources ,systems and monitor.
Anderson
by doing various plans or scheme and providing various kind of free or in less price to the needy people
Madhu
Plx anyone explain bankers draft by giving example.
Shabana
what is price elasticity of demand?
Asamoah Reply
price elasticity of demand is the percentage in quantity demanded of a good or service to the percentage change in its price.
Cobbina
Price elasticity of demand is a measure used in economics to show the responsiveness, or elasticity, of the quantity demanded of a good or service to a change in its price when nothing but the price changes.
TOHEEB
Price elasticity of Demand is a prepotionat change in the demand due to change in price of the goods and service
Dawal
what is monopoly and monopolistic?
KPAAKPA
Price elasticity of demand is the economy measure to show the responsiveness and change in price due to change in quantity.
Lomayani

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Source:  OpenStax, Principles of economics. OpenStax CNX. Sep 19, 2014 Download for free at http://legacy.cnx.org/content/col11613/1.11
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