PRODUCT = Rs.80Markup% = 50% (As he marks a price ASSUMING a profit of 50% on CP)So, Marked Price = Rs.80 + 50% of Rs.80 = Rs.80 + Rs.40 = Rs.120Discount% = 20% So, Selling Price = Marked Price - Discount = Rs.120 - 20% of Rs.120 = Rs.120 - Rs.24 = Rs.96Net Profit = SP - CP = Rs.96 - Rs.80 = Rs.16Hence, NET Profit = Rs.16ALTERNATE SOLUTION:MarkUp% = 50% Discount% = 20%So, Profit% = 50 - 20 - (50 × 20) / 100 = 50 - 20 -10 Profit% = 20%Profit% = 20%CP = Rs.80 20 × 80 = Profit × 100Profit = 1600 ÷ 100 = Rs.16Hence, Net Profit = Rs.16