of price elasticity of demand for a good is:

where is the initial price of the good demanded, is how much it changed, is the initial quantity of the good demanded, and is how much it changed. In other words, we can say that the price elasticity of demand is the percentage change in demand for a commodity due to a given percentage change in the price. If the quantity demanded falls 20 tons from an initial 200 tons after the price rises $5 from an initial price of $100, then the quantity demanded has fallen 10% and the