A cistern can be filled by a tap in 5 hours while it can be emptied by another tap in 8 hours. If both the taps are opened simultaneously, then after how much time will the cistern get filled?	Choose the correct choice from the following answers:  A) 5.2 hrs  B) 13.3 hrs  C) 1.9 hrs  D) 7.2 hrs  E) 1.4 hrs
Net part filled in 1 hour = (1/5 - 1/8) = 3/40   The cistern will be filled in 40/3 hrs i.e., 13.3 hrs.   Answer:13.3 hrs
<result>B</result>
A cistern can be filled by a tap in 5 hours while it can be emptied by another tap in 8 hours. If both the taps are opened simultaneously, then after how much time will the cistern get filled?