By selling 99 pens, a trader gains the cost of 11 pens. Find his gain percentage?
Choose the correct choice from the following:
A) 11 1/3%	B) 11 7/3%	C) 11 1/8%	D) 11 1/3%	E) 11 1/9%
Let the CP of each pen be Rs. 1.   CP of 99 pens = Rs. 99   Profit = Cost of 11 pens   = Rs. 11   Profit% = 11/99 * 100   = 11 1/9%   Answer: 11 1/9%
<result>E</result>
By selling 99 pens, a trader gains the cost of 11 pens. Find his gain percentage?