5.5k views
2 votes
Uppose the demand curve for a product is given by

Q = 10 - 2P + Ps
where P is the price of the product and Ps is the price of a substitute good. The price of the substitute good is ​$2.00.
a. Suppose P = ​$1.00. The price elasticity of demand is_____. ​
b. Suppose the price of the good, P, goes to $2.00. Now what is the price elasticity of demand? What is the cross-price elasticity of demand?

User Corrl
by
5.2k points

2 Answers

5 votes

Final answer:

The price elasticity of demand when P = $1 is -0.2, showing an inelastic demand, whereas at P = $2, it is -0.5, indicating more elastic demand. Furthermore, the cross-price elasticity of demand is 1, implying that the products are substitutes.

Step-by-step explanation:

To determine the price elasticity of demand for a product, we use the formula:

Elasticity of demand (E) = (% Change in Quantity Demanded) / (% Change in Price)

For part a. when P = $1.00:

The initial quantity demanded (Q) is calculated as Q = 10 - 2P + Ps. With P = $1 and Ps = $2, Q = 10 - 2(1) + 2 = 10.

If P increases by a small amount ΔP, then the new quantity demanded Q' = 10 - 2(P + ΔP) + 2. The change in quantity demanded is then ΔQ = -2ΔP.

The price elasticity of demand at P = $1 is E = (ΔQ/Q) / (ΔP/P) = (-2ΔP/10) / (ΔP/1) = -2/10 = -0.2. Therefore, the demand is inelastic at this price point.

For part b. when P = $2:

Q = 10 - 2(2) + 2 = 8. Again, if P increases by ΔP, then Q' = 8 - 2ΔP.

The price elasticity of demand at P = $2 is E = (ΔQ/Q) / (ΔP/P) = (-2ΔP/8) / (ΔP/2) = -0.5, indicating demand is more elastic than at the $1 price point.

To find the cross-price elasticity of demand, which measures how the quantity demanded of one good responds to a change in the price of another good, the formula used is:

Cross-price elasticity of demand (Ec) = (% Change in Quantity Demanded of Good 1) / (% Change in Price of Good 2)

The cross-price elasticity of demand when P goes to $2 is given by the coefficient of Ps in the demand equation, which is 1. Thus, Ec = 1, indicating that the goods are substitutes and the quantity demanded of the product increases when the price of the substitute increases.

User Murat Demir
by
4.9k points
3 votes

Answer:

A. 0.2

B. 0.5, 0.25

Step-by-step explanation:

Q = 10-2p+2

We take like terms

Q= 10+2-2p

= 12-2p

A. If p = 1 dollar

12-2(1)

Q = 10

Price elasticity would be change in quantity divided by the change in price = -2

-2 x p/q

= -2x1/10

= 0.2

Price elasticity of demand is 0.2

B. P = 2 dollars

Q= 10-2x2+2

= 10-4+2

= 8

Price elasticity

= -2x2/8

= 0.5

Cross elasticity

= 1x2/8

= 0.25

User Terrence
by
5.1k points