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# Pouring water IV.

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Pouring water IV. - Back to the Water and Weighing Puzzles

How can you measure 6 liters of water using only 4 and 9-liter bowls?

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Pouring Water IV. - solution

First fill the 9-litre bowl. Then overspill 4 litres to the 4-litre bowl (there are 5 litres in the 9-litre bowl afterwards) and pour out the water from the 4-litre bowl. And again overspill 4 litres to the 4-litre bowl and empty it. Then overspill the remaining litre to the 4-litre bowl but this time keep it there. Fill the 9-litre bowl to the top for the second time and overspill water to fill the 4-litre bowl to the top. Thus the required 6 litres stay in the 9-litre bowl.

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• 2 months later...

Hmmm. . . Couldn't you fill your 4 liter bowl all the way to the top, pour it into the 9-liter bowl, then refil the 4-liter bowl, and tilt it, so that the water line touches the opposite corner of the bottom of the bowl (think barrel), thereby spilling exactly HALF the water, then adding your now TWO liters to the 9-liter bowl, making 6 liters?

That's how I'd do it. . . right or wrong.

WHO'S WITH ME!?

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Nope, Aimster73, think what happens if your vessels are out of shape? think about a vessel that is not cylinder.

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• 2 weeks later...

What about filling up 4 liter, 6 times, and every time pouring it into the 9 liter?

That way 6 liters will spill out.

And we have thus measured out 6 liters.

The problem did not state to have the final result in one of the provided barrels, right?

Let me know who thinks what ...

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What about filling up 4 liter, 6 times, and every time pouring it into the 9 liter?

That way 6 liters will spill out.

And we have thus measured out 6 liters.

The problem did not state to have the final result in one of the provided barrels, right?

Let me know who thinks what ...

whenever you want to measure something, that usually means that you want to have that much. I don't think that when you're cooking and it says to measure one cup of water you spill the one cup of water on the floor...

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You would fill up the 4 container and pour it into the 9 container. You would do this twice.

That makes 8 in the 9 container.

Then fill up the 4 container again and pour it into the 9 container.

That leaves 3 in the 4 container.

You pour out the contents of the 9 container and fill it with the 3 from the 4 contaier.

That leaves 3 in the 9 container.

Then you fill up the 4 container again an pour it into the 9 container.

That makes 7 in the 9 container.

You then fill up the four container and pour it into the 9 container.

That leaves 2 in the 4 container.

You then pour the contents of the 4 container into the emptied 9 container.

That makes 2 in the 9 container.

Then fill up the 4 container and pour it into the 9 container.

That makes 6 in the 9 container.

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Fill up 9con

Poor 9con into 4con - leaving 5 in 9con.

Empty 4con

Poor 5 into 4con - leaving 1 in 9con

Empty 4Con

Poor 1 into 4con

Fill up 9con

Poor 3 from 9con into 4con (1 was already there) - leaving 6 in 9con.

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• 5 weeks later...

I have a question, Does the 4 and 9 liter bowls have measuring marks to tell u if u have 1 liter, 2 liters, and so forth. If so, Then u could fill the 4 liter bowl with water up to the 2 liter mark. Then take the rest of the water and pour it into the 9 liter bowl. In doing this u will see that the water only goes up to the 4 liter mark. Then u add 2 liters and 4 liters to make 6 liters!

That is only if the bowls have measuring marks.

________________

"The only way for evil to triumph, is for good men to do nothing"

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If the bowls have measuring marks then we don't need to do anything gexcept fill the 9 liter container up to where is says 6 liters. About the post that mentions not pouring the water on the floor, why would it suddenly become unusable? He never said it was going onto the floor, he could have anouther caontainer that he can pour it into. But, since he doesn't know the container's volume, he can't use it fore measuring. In cooking, can't you measure some of the water at a time if you need a lot and put that measured water into a bowl of unknown volume?

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Fill up 9con

Poor 9con into 4con - leaving 5 in 9con.

Empty 4con

Poor 5 into 4con - leaving 1 in 9con

Empty 4Con

Poor 1 into 4con

Fill up 9con

Poor 3 from 9con into 4con (1 was already there) - leaving 6 in 9con.

thats exactly what i came up with

0/4

9/9

4/4

5/9

0/4

5/9

4/4

1/9

0/4

1/9

1/4

0/9

1/4

9/9

4/4

6/9

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If the bowls have measuring marks then we don't need to do anything gexcept fill the 9 liter container up to where is says 6 liters. About the post that mentions not pouring the water on the floor, why would it suddenly become unusable? He never said it was going onto the floor, he could have anouther caontainer that he can pour it into. But, since he doesn't know the container's volume, he can't use it fore measuring. In cooking, can't you measure some of the water at a time if you need a lot and put that measured water into a bowl of unknown volume?

No, another vessel is prohibited by the language of the question "using only a 4 liter bowl and a 9 liter bowl."

However, there is a deeper problem with this proposed solution, I'm surprised no one else has picked up on...

What about filling up 4 liter, 6 times, and every time pouring it into the 9 liter?

That way 6 liters will spill out.

Correct me if I'm misunderstanding something, but (4x6)-9=15. So you've correctly "measured" 15 liters onto the floor, not 6. To get 6 liters to spill you must put three volumes of 4 liters into the 9, then empty the 9, rinse and repeat, but how do you distinguish between the 6 you are spilling on purpose and the 9 you are dumping out of necessity?

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im supprised no one else has thought of this, and its much much simpler add two 9quarts to a bowl then remove 3x the 4 quart measurement netting 6 quarts.

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• 1 month later...

I don't think I've seen the solution I came up with:

fill the 4 liter and pour it into the 9

Repeat the above, leaving 8 liters in the 9 container.

Fill the 4 liter again and top off the 9, which subtracts 1 liter from the 4, leaving exactly 3. Pour this 3 into the 6.

Empty the 9 liter and repeat the process (3 x 2=6)

No messy (mental) overpours.

Laurie

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Pour this 3 into the 6.

What 6?

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Oh good grief!

I read the puzzle wrong?!

I'll sit with a dunce cap in the corner...

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• 2 weeks later...
You would fill up the 4 container and pour it into the 9 container. You would do this twice.

That makes 8 in the 9 container.

Then fill up the 4 container again and pour it into the 9 container.

That leaves 3 in the 4 container.

You pour out the contents of the 9 container and fill it with the 3 from the 4 contaier.

That leaves 3 in the 9 container.

Then you fill up the 4 container again an pour it into the 9 container.

That makes 7 in the 9 container.

You then fill up the four container and pour it into the 9 container.

That leaves 2 in the 4 container.

You then pour the contents of the 4 container into the emptied 9 container.

That makes 2 in the 9 container.

Then fill up the 4 container and pour it into the 9 container.

That makes 6 in the 9 container.

thats exactly how i did it, too

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I was blowing Lauries solution away... Then found out, somebody had already taken care of it... Sorry for the unnecessary post...

BoilingOil

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What about filling up 4 liter, 6 times, and every time pouring it into the 9 liter?

That way 6 liters will spill out.

Correct me if I'm misunderstanding something, but (4x6)-9=15. So you've correctly "measured" 15 liters onto the floor, not 6. To get 6 liters to spill you must put three volumes of 4 liters into the 9, then empty the 9, rinse and repeat, but how do you distinguish between the 6 you are spilling on purpose and the 9 you are dumping out of necessity?

I see what sql_er is gettng at... He means exactly what you're actually describing: he first makes three quarts spill by pouring the 4 over in the 9 completely three times. Then he discards the contents of the 9 and does the same again. That gives 6 quarts spilled which he gives as the solution.

The reason why this is REALLY flawed is: there is nothing to capture the spilled water in, since there are ONLY the 4 and 9 quart bowls.

PouringWater

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im supprised no one else has thought of this, and its much much simpler add two 9quarts to a bowl then remove 3x the 4 quart measurement netting 6 quarts.

Which bowl were you going to use to put the 18 quarts in in the first place? You have ONLY the 4 quart and 9 quart bowls, nothing else.

Sorry, flawed.

BoilingOil.

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• 2 weeks later...

take 9 lit

take out 4 lit

add 9 lit

take out 4 lit 2 times

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unless your really gd at estimating or the bowl has marks on it (where u cud just fill the 9 litre up to 6.) i wud do this.

Filll the four litre and pour it into the 9 litre

half fill the four litre and pour it into the 9 litre.

does that work?

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• 3 weeks later...

Use (5) 4 liter containers and (1) 9 liter container.

Fill up the 9 liter container with water

Fill (2) of the 4 liter containers with the water from the 9 liter containers.

Pour the remaining one liter into the 3rd 4 liter container

The 9 liter container will now be empty.

Refill the 9 liter container with water

Fill the last (2) of the 4 liter containers with the water from the refilled 9 liter container.

Pour the remaining one liter into the 3rd 4 liter container ( You will now have 2 liters in the 3rd 4 liter container)

Again the 9 liter container will be empty.

Pour one of the 4 liter containers and the 2 liters from the 3rd 4 liter container into the 9 liter container.

You will now have 6 liters in the 9 liter container.

Nothing hits the floor.

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• 4 weeks later...

Ok yu fill the 9 liter bottle up all the way then pour it into the 4 litter bottle leaving 5 litters in the 9 liter bottle. Then you dump out the 4liter bottle and dump the 9 liter bottle into the 4 liter bottle leaving 1 liter in the 9 litter bottle. Then once again you empty the 4 liter bottle. Then you pour the remaining 1 liter out of the 9 litter bottle into the 4 liter bottle. ok? now you fill the 9 liter bottle up again and dump it into the 4 liter bottle which now contains 1 litter of water so to fill it you would haev to dump 3 liters of water leaving 6 liters in the 9 liter bottle.

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It is unclear as to whether or not you have unlimited water to use and whether or not water can be "measured" onto the floor (which is still measuring)

Assumign you can't do these things.

_______Contents______________________________Contents

Step____B1(4lt)_______Opperation______________B2(9lt)

1._______0____________Fill B2____________________9

2._______4____________Fill B1 from B2_____________5

3._______0____________Empty B1_________________5

4._______4____________Fill B1 from B2_____________1

5._______0____________Empty B1_________________1

6._______1____________Fill B1 from B2_____________0

7._______1____________Fill B2____________________9

8._______4____________Fill B1 from B2_____________6

9._______0____________Empty B1_________________6 Goal Acheived

Popinjay

I wish this thing didn't crop spaces. What a pain.

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• 2 weeks later...

Maybe specifiy more clearly that you are only supposed to use 1 9- litre bowl and 1 4- litre bowl, because the problem just said "9- litre and 4- litre bowls"

Otherwise, there is another solution: Fill 2 9-litre bowls. (Total is now 18). Take out 4 litres from both bowls using the 4-litre bowl. Then empty those bowls. Now, take another 4 litres out of one of the bowls. Now you have one bowl with 5 litres, and the other with 1. Pour 1 into 5. Now you have 6 litres.

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