The cost price of an book is 64% of the marked price. Calculate the gain percent after allowing a discount of 12%? Choose the correct choice from the following:
A) 33%	B) 28.02%	C) 37.5%	D) 30.5%	E) 22%
C   37.5%   Let marked price = $100.   Then, C.P. = $64, S.P. = $88   Gain % = 24/64 * 100= 
<gadget id="calculator">24/64 * 100</gadget>
<output>75/2 = around 37.5</output>
37.5%.
<result>C</result>
The cost price of an book is 64% of the marked price. Calculate the gain percent after allowing a discount of 12%?