Let us suppose that two demand curves have the same slope and different elasticities at a given price. Now see the demand curve JK and LM in given below figure. The demand curve JK and LM both are parallel and thus both have the same slope. Point R on the demand curve JK and point Q on the demand curve LM represents the amount or quantities demanded at a given price, OP.
The elasticity at point R on demand curve JK is RK/RJ and elasticity at point Q on demand curve LM is QM/QL.
It can be proved through the graph that :
Different Elasiticities of Parallel Demand Curves
It can be concluded from the above findings that demand of the same slope curves may vary, and the demand for different slope curves can be similar at a fixed price.
