Dear WmTrevor,

I have been through the "If I asked your two friends 'is the left road the way to heaven?', would my chances be better than asking you?" to no avail.

I think I'm close.

I feel sure there is a hole in it some where, though I'm not sure where exactly, but it seems to work.

Might not you ask any of them the following?

"If I asked 'Is the path to the left the way to heaven?' would you answer me 'Yes'?"

If the answer is 'Yes' take it, if 'No' take the one to the right.

Best I can do for the minute. My brain is about to explode.

Dear Lexi,

Both are great. The best part is even with a big bunch they all get a chance to have some input on problems like this.

This has been a bit of a winner recently;

You have a dozen bags of gold. However one of them has been substituted with counterfeit coins. The only difference to the real ones is they weigh a gram lighter than the others.

You need to find our which bag contains the counterfeit coins but you only have a single set of scales on which you are allowed only one weighing.

How do you tell which bag it is?

"Add iron to?" Don't know, csteele… Are you trying to put your nickname through Google translate? Which for my Latin was all I did with 'to tie horses to'. To the oldie but goodie, you don't need to do any better.

(Houllebecq I was too busy trying to work out the plot of Labyrinth to notice any puzzles - but for the most difficult iteration check out "the hardest logic puzzle" at Wikipedia.)

I went looking for something that was very difficult, practical, could be 'performed' to demonstrate it had been solved/learned and had a touch of 'mind reading' about it. It also allows a small group work and requires planning and partner cooperation to 'work'.

Your students might enjoy this because they can practise it with cards themselves after the solution is provided. I've included the solution because even with the answer the puzzle is still impenetrable.

>>The Card Trick

I ask Alex to pick any 5 cards out of a deck with no Jokers.

He can inspect then shuffle the deck before picking any five cards. He picks out 5 cards then hands them to me (Peter can't see any of this). I look at the cards and I pick 1 card out and give it back to Alex. I then arrange the other four cards in a special way, and give those 4 cards all face down, and in a neat pile, to Peter.

Peter looks at the 4 cards i gave him, and says out loud which card Alex is holding (suit and number). How?

The solution uses pure logic, not sleight of hand. All Peter needs to know is the order of the cards and what is on their face, nothing more."

So there's no mental trauma...

Here is the hint and the answer:
>> There are only 4 suits, so there will be at least two cards of one suit, one higher and another lower. By careful selection and placement the cards can be used to encode the exact number and suit of the selected card.

Answer: Pick out two cards of the same suit. Select a card for Alex where adding a number no greater than six will result in the number of the other card of the same suit. Adding one to the Ace would cycle to the beginning again and result in a Two. E.g. if you have a King and a Six of Diamonds, hand the King to Alex. The other three cards will be used to encode a number from 1 through 6. Devise a system with Peter to rank all cards uniquely from 1 to 52 (e.g. the two of hearts is 1, the two of diamonds is fourteen etc...). That will allow you to choose from six combinations, depending on where you put the lowest and highest cards.<<

The source link: http://www.folj.com/puzzles/very-difficult-analytical-puzzles.htm?5#card

I perceive the logic but I'm going to keep at this until I think I comprehend the answer – but my brain hurts.

Dear WmTrevor,

I'm still a little uneasy about the Limbo guy flipping halfway through but if you are happy I'll take it.

The five card trick is one I used to do with my daughter when she was quite young. Always bedazzles the crowd and for some reason she used to get all the kudos and loved it even though I did all the arranging. Now she is a teenager it is too embarrassing. Will have to wait for grand kids I suppose.

However I never once stopped to think why it worked.

As to the Latin I am going to have to stay away from  cheap translators, Google does indeed return your line. I think I might have been trying to shoe mine.

My favourite puzzle of all time requires no gimmicks just concentration and patience.

It took me over half an hour and is probably the most satisfied I can remember ever being after completing a puzzle.

I will have to rely on a description due to the limitations of the medium but here is my best.

A piece of carpet is 9' x 12' and is solid except for an 8' x 1' hole cut directly in the middle running length ways. The task is to cut it into two pieces only so when it is rejoined it forms a 10' x 10' square solid piece.

Great one for a rainy day.

Thanks all for the contributions thus far. Some have definitely made it into the kit bag.

Dear csteele,

Thanks for this thread.

It's been fun and can be moorish so I'd better
quit while I'm still able to function.
BTW - I know this is a bit off topic -
we went to see the movie - "Margin Call,"
tonight -
starring Kevin Spacey, Jeremy Irons ...
It was advertised as "better than "Wall Street,"
and it did not disappoint.
Excellent cast - and absolutely
riveting. Highly recommend it. If you
haven't already seen it.

How about simple bloody-mindedness like the shredder challenge?

Please excuse embedded retro gamer reference.

Rusty