Bookman purchased 40 copies of a new book released recently, 10 of which are hardback and sold for $20 each, and rest are paperback and sold for $10 each. If 14 copies were sold and the total value of the remaining books was 300, how many paperback copies were sold?	Pick one
A) 6  B) 4  C) 8  D) 10  E) 12
The bookman had 10 hardback ad  40-10= 
<gadget id="calculator"> 40-10</gadget>
<output>30</output>
30 paperback copies;   14 copies were sold, hence  40-14= 
<gadget id="calculator"> 40-14</gadget>
<output>26</output>
26 copies were left. Let # of paperback copies left be p then 10p+20(26-p)=300 --&gt; 10 p=220 --&gt; p=22   # of paperback copies sold is 30-22= 
<gadget id="calculator">30-22</gadget>
<output>8</output>
8   Answer: 8
<result>C</result>
Bookman purchased 40 copies of a new book released recently, 10 of which are hardback and sold for $20 each, and rest are paperback and sold for $10 each. If 14 copies were sold and the total value of the remaining books was 300, how many paperback copies were sold?