P can lay railway track between two stations in 16 days. Q can do the same job in 12 days. With the help of R, they completes the job in 4 days. How much days does it take for R alone to complete the work?  Choose the correct choice from the following choices:  A) 8(3/5) Days  B) 9(3/5) Days  C) 7(3/5) Days  D) 6(3/5) Days  E) 5(3/5) Days
Amount of work P can do in 1 day = 1/16   Amount of work Q can do in 1 day = 1/12   Amount of work P, Q and R can together do in 1 day = 1/4   Amount of work R can do in 1 day = 1/4 - (1/16 + 1/12) = 3/16 – 1/12 = 5/48   =&gt; Hence R can do the job on 48/5 days = 9 (3/5) days   Answer is 9(3/5) Days.
<result>B</result>
P can lay railway track between two stations in 16 days. Q can do the same job in 12 days. With the help of R, they completes the job in 4 days. How much days does it take for R alone to complete the work?