31 replies to this topic

[ALFRED]

haresh that's an interesting way of solving the puzzle. I suppose it's the same as asking how much each tap fills the reservoir in an hour and then finding the solution but it's a different perspective. nice.

[Talha]

are'nt logical puzzles supposed to be logical not mathematical

Edited by Talha, 19 March 2008 - 03:39 PM.

[JTilley]

The simplest answer is within the question.
"the third takes four days"
So, 4 Days.

[vAhi]

days hours % per hour (speed)
a 2.00 48 hrs 0.020833333 = 1/48
b 3.00 72 hrs 0.013888889 = 1/72
c 4.00 96 hrs 0.010416667 = 1/96
d 0.25 6 hrs 0.166666667 = 1/6

Total Speed Per Hour 0.211805556
Time to Fill the 100% 4.721311475 hours = 1/0.211806
283.2786885 minutes

(Done on an Excel spreadsheet)

[palaisipan]

days hours % per hour (speed)
a 2.00 48 hrs 0.020833333 = 1/48
b 3.00 72 hrs 0.013888889 = 1/72
c 4.00 96 hrs 0.010416667 = 1/96
d 0.25 6 hrs 0.166666667 = 1/6

Total Speed Per Hour 0.211805556
Time to Fill the 100% 4.721311475 hours = 1/0.211806
283.2786885 minutes

(Done on an Excel spreadsheet)

Spoiler for Solution

Answer is 12/61. Here is the solution.

Let 1/2 be work A can do in a day/ Let 1/3 be the work B can do in a day. Let 1/4 be the work C can do in a day. Let 4 be the work D can do in a day.

=> X(1/2 + 1/3 + 1/4 + 4) = 1
=> X=1/(1/2 + 1/3 + 1/4 + 4)
=> x=12/61

[qwert]

I probably just don't get this, but how do you fill up a resevoir with four taps that empty it??

[Martini]

I probably just don't get this, but how do you fill up a resevoir with four taps that empty it??

The taps are used to fill the reservoir, not empty it. The taps get their water from another source.

[EPISTAXIS]

without a size or volume or an amount equal to full i cant really understand this one, but i know that it will be less than six hours. due to the fact that the last one can do it in 6hrs the others are also adding water at the same time constantly making the amount that is empty smaller as the full amount in six hours is being assisted by the slower faucets or spigots. i think i spelled spiggotts right. lol

[verdeblahblah]

8 days 6 hrs to fill up :melow:

[EaseZ]

The answer is as found by many, 4.72 hours. But I'm wondering how anyone could come up with an result greater than 6 hours. Unable to do the math, understandable, but such a failure of logic, that's bewildering. Misreading the question?