Answer:
PED = 0.67 inelastic demand
you should not lower the price of the book
Explanation:
the midpoint formula for calculating price elasticity of demand = {(Q2 - Q1) / [(Q2 + Q1) / 2]} / {(P2 - P1) / [(P2 + P1) / 2]}
PED = {(50 - 40) / [(50 + 40) / 2]} / {(25 - 35) / [(25 + 35) / 2]} = [10 / (90 / 2)] / [-10 / (60 / 2)] = (10 / 45) / (-10 / 30) = 0.222 / -0.333 = 0.67
the PED = 0.67 which means that the demand is inelastic
if you lower the price of the book, the increase in number of books sold will be proportionally lower than decrease in price, so you will lose money by doing that.