A is half good a work man as B and together they finish a job in 12 days. In how many days working alone B finish the job?  Choose the correct choice from the following answers:
A) 28 days
B) 22 days
C) 20 days
D) 18 days
E) 19 days
WC = 1:2   2x + x = 1/12 =&gt; x = 1/36   2x = 1/18 =&gt; 18 days   ANSWER:18 days
<result>D</result>
A is half good a work man as B and together they finish a job in 12 days. In how many days working alone B finish the job?