The C.P of 10 pens is equal to the S.P of 12 pens. Find his gain % or loss%? Choose the correct option
A) 16 2/7%	B) 16 6/3%	C) 16 2/3%	D) 16 1/3%	E) 12 2/3%
10 16 2/3%P = 12 SP   12 --- 2 16 2/3%P loss   100 --- ? =&gt; 16 2/3%   Answer: 16 2/3%
<result>C</result>
The C.P of 10 pens is equal to the S.P of 12 pens. Find his gain % or loss%?