Question

8 pipes are required to fill a tank in 1 hr 20 min. How long will it take if 6 pipes of the same types are used ?
( direct and inverse proportion )

Answer 1

It is given that 8 pipes are required to fill a tank in 1 hr 20 min

We have to find out the time taken by 6 pipes.

In order to find out the time taken by 6 pipes,we will use inverse proportion

1 hr 20 min = 80 minutes

Time taken by 8 pipes = 80 minutes

Time taken by 6 pipes = $80 \times \frac{8}{6}$

                                      = 106.66

6 pipes will take 106.66 minutes to fill the tank.

Answer 2

Given,

$8$ pipes are required to fill a tank in $1$ hour $20$ minutes.

We have to find the how much time will take $6$ pipes

Here,

$8$ pipes are required to fill a tank in $1$ hour $20$ minutes, we have to convert the time hours into minutes.

$1$ hour $=60$ minutes

So,

$1$ hour $20$ minutes $= 60+20$

$= 80$ minutes

we have to find the one pipe fill tank in how much time

$1$ pipe fill tank $= \frac{80}{8}$

So, one pipe fill time multiply with six pipe, we get

$= 6\times\frac{80}{8}$

$= 60$ minutes

Therefore, the answer is $60$ minutes.