[rookie1ja]

Filling the Pool - Back to the Logic Puzzles
A swimming pool has four faucets. The first can fill the entire pool with water in two days, the second – in three days, the third – in four days, and the last one can fill the pool in 6 hours.
How long will it take to fill the pool using all 4 faucets together?

Spoiler for Solution:

Reservoir - solution
Because there are 24 hours in one day, in one hour fills the first tap 1/48, the second tap 1/72, the third tap 1/96 and the fourth tap fills 1/6 of the reservoir. That is all together (6+4+3+48) / 288 = 61/288. The reservoir will be full in 288/61 hours, which is 4 hours 43 minutes and about 17 seconds.

Spoiler for old wording:

One reservoir has four taps. Using the first takes two days to saturate the reservoir, the second tap three days, the third four days and the last one 6 hours. How long will it take to fill the reservoir using all 4 taps at once?

[natterbox]

i divided them all by 4 and added them up to get 2 days and 7 hours

[Stephanie]

I did it in the same way as rookie1ja, and got approximately 4 hrs and 44 minutes.. little bit less, actually.

How did you get that solution with more than 2 days?

[larryhl]

natterbox, if all 4 taps are working together, you need to get a time less than 6 hours >< tap 4 can't do the whole job faster than all 4 working together.

as a decimal, the time is approximately 4.72 hours.

[dak1530]

i came up with 4.73 hrs or 4 and 44 minutes

[lukegaru]

4.72hours

[savagegamer90]

I got 4.72 hours as well

[lucid]

The answer is precisely 12/61 days.

A = 1/2 (reservoirs/day)
B = 1/3
C = 1/4
D = 4

(A + B + C + D) * Time = 1 (Time is in days. A, B, C, and D are in reservoirs per day.)
(1/2 + 1/3 + 1/4 + 4) * Time = 1
(61 / 12) * Time = 1
Time = 12 / 61 days (~ 4.72 hours)

[tealuvr104]

2 days = 48 hours = x
3 days = 72 hours = y
4 days = 96 hours = z
6 hours = a

(x + y)/2= 60
(60+ z)/2=78
(78+6)/2=42

Answer= 42 hours

[PMitra]

First of all we will calculate per hour work done by each tap like-

1st tap will fill the reservior by 1/48 in an hour.
2nd tap will fill it 1/72
3rd will fill 1/96 part of the reservior in an hour.
and 4th will fill 1/6

now sum of all four taps if all are open simultaneously will be- 61/288

which gives the answer as- all four taps if open simultaneously will put the reservior in eq state in 4 hours 43 minutes and 2** seconds... ( Is that okay )