I sold a book at a profit of 10%. Had I sold it for $150 more, 15% would have been gained. Find the cost price?
Choose the correct choice from the following.
A) $2000 B) $2500 C) $3000 D) $3120 E) $1540
115% of cost - 110% of cost = $150   5% of cost = $150   cost = 150*100/5= 
<gadget id="calculator">150*100/5</gadget>
<output>3_000</output>
$3000   Answer is $3000
<result>C</result>
I sold a book at a profit of 10%. Had I sold it for $150 more, 15% would have been gained. Find the cost price?