Given, original price of microwave oven =$2500
discount price of microwave oven =$1500
∴Percentage of discount = Original price - Discount priceOriginal price×100%
=2500−15002500×100%
=10002500×100%
=2×5×1005×5×100×100%
=25×100%
=2×1005%
=2×5×205%
=2×20%
=40%
Hence, shopkeeper gave a discount of 40%.