quantity demanded of a commodity rises by 6 units when its price falls by rs 1 per unit. its price elasticity of demand is -1. if the price before the change was rs 20 per unit calculate quantity demanded at this price.
Change in quantity, i.e., ΔQ = 6
Change in price, i.e., ΔP = -1
Elasticity of demand, Ed = -1
Original price, P = 20
So, by applying the formulae for elasticity of demand
