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Truth in packaging


Best Answer Aaron Burr , 03 September 2007 - 04:15 PM

Perhaps?
The only way this works is to assume all the boxes are in fact wrong. First draw from the [box 3] nails and screws. You will get either a nail or a screw. You will label it as which ever you draw out. Let's say it's a nail. The [box 1] nails can not contain nails so it must contain the screws. The [box 2] screws must there for be the mixture. In short:
[box 1] screws
[box 2] nails and screws
[box 3] nails

'No excuses!' We cannot shift that burden onto God, or nature, or the ways of the world Go to the full post


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32 replies to this topic

#31 achia

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Posted 22 January 2010 - 08:10 PM

Sunkissed.

Congratulations. Very clearly explained.
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#32 keyholder

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Posted 31 January 2010 - 07:03 AM

This one's fairly easy.

Spoiler for Solution and only solution:

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#33 mojobrain

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Posted 02 February 2010 - 07:44 AM

Spoiler for
Spoiler for
Spoiler for
We know all the boxes are incorrectly labelled.

We know we can't shake the boxes, look into them or take out more than one item.

There is no rule, however, stating that we cannot feel around inside the chosen box when we reach inside it.

Reach into the box labelled "Screws". Since we know it's mislabelled, it would have to contain either Nails or Nails & Screws. Since the nails would be thinner, they would drift to the bottom of the box, & the screws would be on top. Ergo, if you reached in & were able to feel a number of nails, you would know it should be labelled "Nails". If you felt screws & knew the box was mislabelled, you would know to label it "Nails & Screws".

Taking the first case as an example, remove the Screws label from Box 2. Then take the Nails label from Box 1 and place it on Box 2. Since Box 3 is also incorrectly marked, and Box 2 is now OK, you just switch the label on Box 3 to Box 1 & put the Screws label on Box 3.[/spoiler]
Spoiler for
We know all the boxes are incorrectly labelled.

We know we can't shake the boxes, look into them or take out more than one item.

There is no rule, however, stating that we cannot feel around inside the chosen box when we reach inside it.

Reach into the box labelled "Screws". Since we know it's mislabelled, it would have to contain either Nails or Nails & Screws. Since the nails would be thinner, they would drift to the bottom of the box, & the screws would be on top. Ergo, if you reached in & were able to feel a number of nails, you would know it should be labelled "Nails". If you felt screws & knew the box was mislabelled, you would know to label it "Nails & Screws".

Taking the first case as an example, remove the Screws label from Box 2. Then take the Nails label from Box 1 and place it on Box 2. Since Box 3 is also incorrectly marked, and Box 2 is now OK, you just switch the label on Box 3 to Box 1 & put the Screws label on Box 3.[/spoiler]
Spoiler for
Spoiler for
We know all the boxes are incorrectly labelled.

We know we can't shake the boxes, look into them or take out more than one item.

There is no rule, however, stating that we cannot feel around inside the chosen box when we reach inside it.

Reach into the box labelled "Screws". Since we know it's mislabelled, it would have to contain either Nails or Nails & Screws. Since the nails would be thinner, they would drift to the bottom of the box, & the screws would be on top. Ergo, if you reached in & were able to feel a number of nails, you would know it should be labelled "Nails". If you felt screws & knew the box was mislabelled, you would know to label it "Nails & Screws".

Taking the first case as an example, remove the Screws label from Box 2. Then take the Nails label from Box 1 and place it on Box 2. Since Box 3 is also incorrectly marked, and Box 2 is now OK, you just switch the label on Box 3 to Box 1 & put the Screws label on Box 3.

Ireally did this off the top of my head - hope I'm not missing something.
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