Question

Pipe a can fill a tank in 8 hours and pipe b can fill it in 6 hours. If both the pipes are opened but after 2 hours pipe a is closed, then the other pipe will fill the tank in

Answer 1

Answer:

2.5 Hrs

Step-by-step explanation:

Pipe a fill tank in 8 hrs

Pipe a fill tank in 1 hrs = $\frac{1}{8}$

Pipe b fill tank in 6 hrs

Pipe b fill tank in 1 hrs = $\frac{1}{6}$

Pipe a+b fill tank in 1 hrs = $\frac{1}{8}$ +  $\frac{1}{6}$

Pipe a+b fill tank in 1 hrs = $\frac{3+4}{24}$

Pipe a+b fill tank in 1 hrs = $\frac{7}{24}$

Pipe a+b fill tank in 2 hrs = $\frac{7}{12}$

Tank remained to fill =  1 - $\frac{7}{12}$

Tank remained to fill =  $\frac{12-7}{12}$

Tank remained to fill =  $\frac{5}{12}$

Time taken by pipe b to fill remaining = $\frac{5}{12}$ / $\frac{1}{6}$

= 2.5 Hrs