The C.P of 10 pens is equal to the S.P of 15 pens. Find his gain % or loss%?	Select
A) loss 16 2/8%	B) loss 16 6/3%	C) loss 16 2/3%	D) loss 18 2/3%	E) loss 33.33%
10 CP = 15 SP   15 --- 5   100 --- ? =&gt; 33.33% (Loss)   Answer:loss 33.33%
<result>E</result>
The C.P of 10 pens is equal to the S.P of 15 pens. Find his gain % or loss%?