A swimming pool has four faucets.
They fill the pool in following times :
1. The first can fill the entire pool with water in two days,
2. The second in three days,
3. The third in four days, and
4. The last one can fill the pool in 6 hours.
How long will it take to fill the pool using all 4 faucets together?
Since there are 24 hours in one day,
in one hour first tap fills 1/48,
the second tap 1/72,
the third tap 1/96 and
the fourth tap fills 1/6 of the Pool.
That is all together (6+4+3+48) / 288 = 61/288.
The Pool will be full in 288/61 hours,
which is 4 hours 43 minutes and about 17 seconds.