A can do a piece of work in 4 hours . A and C together can do it in just 2 hours, while B and C together need 3 hours to finish the same work. B alone can complete the work in --- hours.  Select.
A) 10 B) 12 C) 14 D) 16 E) 18
Work done by A in 1 hour = 1/4   Work done by 12 and C in 1 hour = 1/3   Work done by A and C in 1 hour = 1/2   Work done by A,12 and C in 1 hour = 1/4+1/3 = 7/12   Work done by 12 in 1 hour = 7/12 – 1/2 = 1/12 =&gt; 12 alone can complete the work in 12 hours   Answer is 12.
<result>B</result>
A can do a piece of work in 4 hours . A and C together can do it in just 2 hours, while B and C together need 3 hours to finish the same work. B alone can complete the work in --- hours.