Question

10. Two pipes can fill a tank in 4 hours and 8 hours respectively, while a third
pipe empties the full tank in 12 hours. If all the three pipes are operated
simultaneously how long will it take for the tank to be full​

Answer 1

Given that pipe A can fill a tank in 10 hours

=> In one hour it fills 1/10th part of the tank ( by cross multiplication method)

And pipe B can fill a tank in 12 hours

=> In one hour it fills 1/12th part of the tank.

And also given pipe C empties the tank in 20 hours => in one hour it empties 1/20th part.

If all three pipes operate simultaneously work done by both pipes A and B in one hour will be added and C work is subtracted.

Therefore work done by three pipes in one hour = 1/10 + 1/12 -1/20 = 8/60

In 1 hour 8/60th part of a tank can be filled.

Then complete tank can be filled in 60/8 = 7.5hrs

( by cross multiplication

Answer 2

Step-by-step explanation:

ʜᴏᴩᴇ ɪᴛ ᴡɪʟʟʟ ʜʀʟᴩᴩᴩᴩᴩᴩ ɪᴜᴜᴜᴜᴜ