Answer:
(a)20
(b)Elastic
(c)8
(d) Elastic
Step-by-step explanation:
Elasticity of demand(E) indicates the impact of a price change on a product's sales.
The general formula for an exponential demand curve is given as:
[tex]y=ae^{-bp}[/tex]
Given the demand curve formula
[tex]q=f\left(p\right)=200e^{-0.4p}[/tex]
The formula for Elasticity of demand, E
[tex]E = -\dfrac{p}{q}\dfrac{\text{d}q}{\text{d}p}[/tex]
(a)When Price, p = $50
p=50
[tex]q=200e^{-0.4*50}=200e^{-20}[/tex]
[tex]\dfrac{\text{d}q}{\text{d}p}=-0.4*200e^{-0.4p}=-80e^{-0.4p}[/tex]
Therefore:
[tex]E = -\dfrac{50}{200e^{-20}}*-80e^{-0.4*50}\\=\dfrac{1}{4e^{-20}}*80e^{-20}\\\\E=20[/tex]
(b)At p = $50, Since elasticity is greater than 1, the demand is elastic.
An elasticity value of 20 means that a 1% increase in price causes a 20% decrease in demand.
(c)At p=$20
p=20
[tex]q=200e^{-0.4*20}=200e^{-8}[/tex]
[tex]\dfrac{\text{d}q}{\text{d}p}=-0.4*200e^{-0.4p}=-80e^{-0.4p}[/tex]
Therefore:
[tex]E = -\dfrac{20}{200e^{-8}}*-80e^{-0.4*20}\\=\dfrac{1}{10e^{-20}}*80e^{-20}\\\\E=8[/tex]
(d)At p = $20, the demand is elastic.
An elasticity value of 8 means that a 1% increase in price causes a 8% decrease in demand.