The C.P of 15 books is equal to the S.P of 18 books. Find his gain% or loss%?  Choose the correct choice from the following answers.
A) 16 2/3%
B) 16 2/7%
C) 16 0/3%
D) 18 2/3%
E) 26 2/3%
15 CP = 18 SP   18 --- 3 CP loss   100 --- ? =&gt; 16 2/3% loss   16 2/3%nswer: 16 2/3%
<result>A</result>
The C.P of 15 books is equal to the S.P of 18 books. Find his gain% or loss%?