A dealer offers a cash discount of 10% and still makes a profit of 35% when he further allows 20 articles to be sold at the cost price of 15 articles to a particular sticky bargainer. How much percent above the cost price were his articles listed? Options:
A) 80 %	B) 100 %	C) 120 %	D) 60 %	E) 90 %

Rationale: "given cash discount - 10 % profit - 35 % items sold - 20 price sold at = list price of 15 assume list price = $ 20 total invoice = $ 300 - 10 % cash discount = $ 270 let cost price of 20 items be x so total cost = 20 * x given the shopkeeper had a profit of 20 % 20 * x * 135 / 100 = 270 or x = $ 10 which means his products were listed at $ 20 which is a 100 % markup over $ 10 answer b"
Answer: B