The two buckets, 4 gallons of water question...

[mjr]

I'm sure many of you have heard this question.

You have two buckets, one 3 gallon and one five gallon, and a water hose. I'm talking about U.S. gallons, here.

You want to get 4 gallons of water.

How do you do it?

The question is something like that.

Most of us know the answer, but would it be cheating if you used the fact that a U.S. Gallon weighs approximately 8.3 pounds, and therefore you could weigh the five gallon bucket, set that at 0, and fill the bucket (while the bucket is on a scale) with just over 33 pounds of water?

I also came up with a simple math formula for this.

Let V1 = 3
Let V2 = 5

R is the result.

So, R = (2(V1) - V2) + V1

If you plug in the numbers, you get:

R = [2(3) - 5] + 3
R = (6 - 5) + 3
R = 1 + 3
R = 4

[csquared]

Fill the 5 gallon bucket. Pour out the water into the 3 gallon bucket. You are left with 2 gallons in the 5 gallon bucket.
Repeat the process.

[Chromatix]

Right, but you need a third bucket to hold the 2 gallons for the moment. You also waste a total of 6 gallons of water.

Better idea:

Fill the 3-gallon bucket.

Empty it into the 5-gallon bucket.

Fill the 3-gallon bucket again.

Use it to fill the 5-gallon bucket to the top.

Empty the 5-gallon bucket.

There is now 1 gallon in the 3-gallon bucket. Empty it into the 5-gallon bucket.

Fill the 3-gallon bucket one final time.

Empty it into the 5-gallon bucket. That now contains 4 gallons, and you have wasted only 5 gallons of water.

[Brandy]

Why not just divide the 5 gallon bucket into 1/5ths-measure the height, divide by 5 and mark each 1/5th with a line. Then fill up 4/5ths of the bucket. Now you have 4 gallons and no wasted water. If done correctly, each equal 1/5th should be 1 gallon.

[BroSCFischer]

Why not just divide the 5 gallon bucket into 1/5ths-measure the height, divide by 5 and mark each 1/5th with a line.

Most buckets these days have a wider mouth than base which would throw the measurements off. Chromatix actually gave the traditional solution to the problem.

SC

[Seraph]

Take both buckets, chuck them back into the shed, and go to the store and get four gallon jugs.

[Brandy]

Most buckets these days have a wider mouth than base which would throw the measurements off. Chromatix actually gave the traditional solution to the problem.

SC

Hmm, the 5 gallon bucket I have is not shaped like that, its just straight up and down, but ok. Of course, I like Seraph's idea of just getting the 4 gallon jugs

[Seraph]

Hmm, the 5 gallon bucket I have is not shaped like that, its just straight up and down, but ok. Of course, I like Seraph's idea of just getting the 4 gallon jugs

...I think outside of normal parameters.

[Jay 2K Winger]

Whatever you do, once you have that 4 gallons of water, make sure to use it to defuse that bomb. Then make sure to take that bomb with you. Some kid could come along, and...


Cookie for reference.

[Bright_Star]

Watch "Die Hard With A Vengeance". The answer is in the movie...lol.

[Seraph]

I just found out that it's from a movie. I've only seen Die Hard 1, 4, and 5, so...yeah. I need to fill in that gap there.

[MoonCat]

I would go back in the house, get a half gallon or one gallon plastic jug out of the recycling box, and either fill the half gal. one 8 times or the one gallon one four times, dumping the water into the 5 gal. bucket each time the jug was filled. Wouldn't waste any water that way.

[wolfie]

Alternate solution:

Fill the 5 gallon bucket.

Pour from the 5 gallon bucket into the 3 gallon bucket until it's full. You now have 2 gallons in the 5 gallon bucket.

Dump out the 3 gallon bucket, then pour the remaining 2 gallons into the 3 gallon bucket.

Fill the 5 gallon bucket again, and pour from it into the 3 gallon bucket until it's full. Since the 3 gallon bucket already had 2 gallons in it, that means it will take 1 more gallon to fill, leaving you with 4 gallons in the 5 gallon bucket.

[Chromatix]

Yes, that works - but you still waste 6 gallons rather than 5. You've only poured away 3 gallons, true, but you have 3 gallons left over that you're not carrying.

[Sonoma]

Or, I'll just use my horse's water bucket, which has measurements on the side <G>