Price Elasticity of Demand (Ed) = Percentage Change in Quantity Demanded / Percentage Change in Price
(-)0.2 = -10 / Percentage Change in Price
Percentage Change in Price = -10 / -0.2 = 50%
Calculation of New Price: price has increased by 50%
New Price = 1 + 50% of 1 = 1 + 0.50 = 1.50 rupee