12 persons can complete the work in 18 days. after working for 6 days, 4 more persons added to complete the work fast. in how many more days they will complete the work?
Pick
A) 10 days B) 9 days C) 8 days D) 7 days E) 6 days
total work 12*18= 
<gadget id="calculator">12*18</gadget>
<output>216</output>
216 units   after 6 days work finished   6*12= 
<gadget id="calculator">  6*12</gadget>
<output>72</output>
72 units   remaining work 216-72= 
<gadget id="calculator">216-72</gadget>
<output>144</output>
144 units   remaing days=144(12+4)=9 days   ANSWER:9 days
<result>B</result>
12 persons can complete the work in 18 days. after working for 6 days, 4 more persons added to complete the work fast. in how many more days they will complete the work?