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Suppose that ‘Myer’ sells two brands of jeans: Levi Jeans and Lee Jeans. You are given the following data,
use the mid-point formula for any calculations of elasticity. All data are per day.
Levi Jeans Lee Jeans

Price Quantity Price Quantity Wage Rate of customers
Sept 14 $120 21 $120 24 $225
Sept 15 $130 19 $120 26 $225
Sept 16 $130 21 $120 29 $250
Sept 17 $120 22 $130 28 $250
a) What is price elasticity of demand and what are the factors that influence the price elasticity of
demand of jeans? How is price elasticity of demand calculated?
b) Assume that we are only considering the data above. Is it possible to pinpoint why the quantity
demanded of Levi Jeans has changed between September 14 and September 15? If so, explain what
happened. If not, explain why. Remember to consider ceteris paribus conditions.
c) Calculate the price elasticity of demand for Levi Jeans between September 14 and September 15.
d) Assume that we are only considering the data above. Is it possible to pinpoint why the quantity
demanded of Lee Jeans has changed between September 16 and September 17? If so, explain what
happened. If not, explain why. Remember to consider ceteris paribus conditions.