Question

This pipe B can fill the tank in 40 minutes and can be filled in 80 minutes. Pipe B was closed after two pipes were cut. What if the total time to fill the bank is 30 minutes? How much time

Pipe B is opened​

Answer 1

Step-by-step explanation:

Let the second pipe be closed after x minutes.

Then,

3 0

2 4

+

40

x

=

1

⇒

120

96+3x

= 1⇒ 3x= 120− 96= 24⇒ x=

8 min