A dishonest trader marks up his goods by 80% and gives discount of 25%. Besides he gets 20% more amount per kg from wholesaler and sells 10% less per kg to customer. What is the overall profit percentage?

Answer: Option D

CP = $$\frac{100}{120}=\frac{10}{12}$$   [Since, he purchases 120 g and pays Rs. 100, by assumption actual CP of 1 g = Re. 1]
SP = $$\frac{135}{90}=\frac{3}{2}=\frac{18}{15}$$    [Since, Actual MP = 180 as he mark up 80% above, SP = 135, with 25% discount and he sells 90 g instead of 100g]
Percentage Profit = $$\frac{\frac{18}{12}-\frac{10}{12}}{\frac{10}{12}}\times 100=80\%$$