Learning Contents:                                                              ·          Calculating Income elasticity using Arc elasticity method( Practical Questions) Income Elasticity of Demand (Arc Elasticity or Midpoint method) Generally, the arc represents a portion or segment of some curve shape. When income elasticity is to be measured over a certain range or between two points on the income demand curve, we use arc- income elasticity method. It is also known as midpoint method. Unlike the proportionate method that uses the initial income and initial quantity in denominator (or base); this method uses the average of both income and quantity in denominator (or base) for finding the elasticity. Therefore, when using arc elasticity, we need not to be worried about which point is the starting point and which point is the ending point since it gives same results whether income rises or falls. The formula used to calculate the income elasticity of demand using arc method is