Question

Pipe a can fill a tank in 8 hours. when it works along with pipe b, it can fill the tank in 6 hours. in how many hours can pipe b fill the same tank independently

Answer 1

in 1h A can fill 1/8part of the whole tank
in 1h (A+B)can fill 1/6....................................
in 1h B can fill 1/6-1/8....................................
= 1/24......................................
then, B can fill the tank in 24hours