A man buy a book in Rs50 & sale it Rs70. What is the rate of profit ??? Choose the correct choice:
A) 10%	B) 40%	C) 30%	D) 25%	E) 28%
cp=50   sp=70   profit=70-50= 
<gadget id="calculator">70-50</gadget>
<output>20</output>
20   %=20/50*100= 
<gadget id="calculator">20/50*100</gadget>
<output>40</output>
40%   ANSWER:40%
<result>B</result>
A man buy a book in Rs50 & sale it Rs70. What is the rate of profit ???