If a commission of 10% is given on the marked price of a book, the publisher gains 20%. If the commission is increased to 15%, the gain is:	Pick one.
A) 16(2/3)%
B) 13(1/3)%
C) 15 (1/6)%
D) 15%
E) None of these
Let C.P.=Rs. 100. First S.P.=Rs. 120   Now, S.P. =Rs. 120, commission=10%   Therefore, Marked Price=[(100/90)X120]=Rs. 400/3.   No, marked price=400/3, commission=15%   Therefore, S.P.=85% of 400/3=[(85/100)X(400/3)]=340/3.   Therefore, Gain%=[(340/3)-100]=40/3=13(1/3)%.   ANSWER:13(1/3)%
<result>B</result>
If a commission of 10% is given on the marked price of a book, the publisher gains 20%. If the commission is increased to 15%, the gain is: