There is a huge water tank and there are four pipes that can fill the water tank.
> The first pipe can fill the water tank completely in exact 2 days.
> The first pipe can fill the water tank completely in exact 3 days.
> The first pipe can fill the water tank completely in exact 4 days.
> The first pipe can fill the water tank completely in exact 6 hours
Let's say we opened all the pipes simultaneously, how long will it take the water tank to be filled completely?
288/61 hours (4 hours, 43 minutes and 17 seconds approx)
In 1 hour, the ratio of water tank filled by pipes:
1st pipe: 1/48
2nd pipe: 1/72
3rd pipe: 1/96
4th pipe: 1/6
All togther
1/48 + 1/72 + 1/96 + 1/6
=> (6+4+3+48) / 288 = 61/288.
=> 288/61 hours,
which is 4 hours 43 minutes and about 17 seconds.
