Answer:
a) the ratio of the percentage change in quantity demanded to the percentage change in price.
Step-by-step explanation:
The formula of the price elasticity of demand is shown below:
= (change in quantity demanded ÷ average of quantity demanded) ÷ (percentage change in price ÷ average of quantity demanded)
Change in quantity demanded would be
= Q2 - Q1
And, average of quantity demanded would be
= (Q1 + Q2) ÷ 2
Change in price would be
= P2 - P1
And, average of price would be
= ($P1 + P2) ÷ 2