A dealer offers a cash discount of 10% and still makes a profit of 20% when he further allows 45 articles to be sold at the cost price of 40 articles to a particular sticky bargainer. How much percent above the cost price were his articles listed?  Choose the correct choice from the following options:
A) 40%
B) 50%
C) 55%
D) 80%
E) 90%
Given   Cash Discount - 10%   Profit - 20%   Items Sold - 45   Price Sold at = List Price of 40   Assume List price = $10   Total Invoice = $400   -10% Cash Discount = $360   Let cost price of 45 items be x   So total cost = 45*x   Given the shopkeeper had a profit of 20%   45 * x * 120/100 = 360   or x = $20/3=$6+(2/3)   Which means his products were listed at $10 which is a 50% markup over $6+(2/3)   Answer 50%
<result>B</result>
A dealer offers a cash discount of 10% and still makes a profit of 20% when he further allows 45 articles to be sold at the cost price of 40 articles to a particular sticky bargainer. How much percent above the cost price were his articles listed?