Answer:
2.2
Explanation:
The formula for calculating price elasticity using the midpoint method is:
midpoint method = {(Q2 - Q1) / [(Q2 + Q1) / 2]} / {(P2 - P1) / [(P2 + P1) / 2]}
midpoint method = {(150 - 100) / [(150 + 100) / 2]} / {(1.20 - 1) / [(1.20 + 1) / 2]}
midpoint method = [50 / (250 / 2)] / [0.20 / (2.20 / 2)] = (50 / 125) / (0.20 / 1.1)
midpoint method = 0.4 / 0.19 = 2.2
The advantage of using the midpoint method to calculate price elasticity is that we can calculate the price elasticity between two points, and it doesn't matter if the price increases or decreases.
If we calculate price elasticity using the single point formula:
price elasticity = % change in quantity supplied / % change in price = 50% / 20% = 2.5