A furniture store owner decided to drop the price of her recliners by 20% to spur business. By the end of the week she had sold 60% more recliners. What is the percentage increase of the gross?
Choose the correct choice.
A) 10 % B) 15 % C) 20 % D) 28 % E) 50 %

Rationale: "say a recliner is actually worth $ 100 if she sells 100 recliners then she earns $ 10000 after the discount of 20 % , she will earn $ 80 per recliner and she sells 60 % more ie . , 160 recliners hence her sales tields 160 * 80 = $ 12800 increase in sales = 12800 - 10000 = $ 2800 so % increase = 2800 * 100 / 10000 = 28 % d is the answer"
Answer: D