A can do a piece of work in 15 days and B in 20 days. They began the work together but 5 days before the completion of the work, A leaves. The work was completed in? Answers.
A) 15 3/7 days	B) 11 3/7 days	C) 12 3/7 days	D) 19 3/7 days	E) 13 3/7 days
11 3/7 days   11 3/7 days   (x – 5)/15 + x/20 = 1   x = 11 3/7 days
<result>B</result>
A can do a piece of work in 15 days and B in 20 days. They began the work together but 5 days before the completion of the work, A leaves. The work was completed in?