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Siustrulka
Mar 30, 2007, 03:21 PM
There are three colored jars each containing two marbles. One jar contains two black marbles another contains one black marble and one white marble and the last jar contains two white marbles. The jars are labeled BB BW AND WW but all of them are mislabeled. What is the smallest number of marbles you must remove in order to determine the correct contents of the jars?

Curlyben
Mar 30, 2007, 03:30 PM
Why remove any when all you need to do is open the jar and look in, but if they are clear glass then you don't even need to do that. Simply look through the side.

worthbeads
Mar 30, 2007, 04:21 PM
4, and maybe 3 if you're lucky. Am I right?

Otherwise, I would agree with Curlyben. Maybe next time you can say the marbles are in cloth bags.

Capuchin
Mar 30, 2007, 11:58 PM
One.
Take a marble out of the box labeled BW. If it is white, then WW is in that box, BB is in the box labeled WW and BW is in the box labeled BB.
If the marble you take out of BW is black then BB is in that box, WW is in the box labaled BB and BW is in the box labeled WW.

It works, trust me. You need to remember that the jars are not randomly labeled, they are incorrectly labeled.

Siustrulka
Mar 31, 2007, 07:49 PM
One.
Take a marble out of the box labeled BW. if it is white, then WW is in that box, BB is in the box labeled WW and BW is in the box labeled BB.
If the marble you take out of BW is black then BB is in that box, WW is in the box labaled BB and BW is in the box labeled WW.

It works, trust me. You need to remember that the jars are not randomly labeled, they are incorrectly labeled.


Can you explain how you got that answer...

Capuchin
Apr 1, 2007, 04:12 AM
I worked it out in my head??

Do you not follow my logic?

Siustrulka
Apr 1, 2007, 06:32 AM
I worked it out in my head???

Do you not follow my logic?


Not really

worthbeads
Apr 1, 2007, 06:48 AM
The main thing is what Capuchin put last. The jars are not labeled randomly, but incorrectly. Jar WB cannot contain a white and black marble because it is labeled incorrectly. So whatever color marble you pick out of WB will determine its label; e.g. picking a white marble means both marbles in that jar are white. Then determine which jar is which with the two remaining jars.

Capuchin
Apr 1, 2007, 06:54 AM
I'm glad you agree with me worth :)

You have to choose to take one out of the one labeled BW, because that one is guaranteed to either have BB or WW in it. Whatever ball you take out of it will tell you what it is.

Then, you can easily determine where the other double colored balls are, they're in the one not labelled with their name.

Then that leaves BW to be in the final box.

Siustrulka
Apr 1, 2007, 10:08 AM
I'm glad you agree with me worth :)

You have to choose to take one out of the one labeled BW, because that one is guaranteed to either have BB or WW in it. Whatever ball you take out of it will tell you what it is.

Then, you can easily determine where the other double colored balls are, theyre in the one not labelled with their name.

Then that leaves BW to be in the final box.

Thank you I get it :):):):):)