The worlds first riddle!

The second puzzle is old hat.

The first is more intriguing -- but if they are "compensating for the inequities of their marksmanship skills" -- why does the best shot go second rather than third?

The order in which they shoot, was determined by the time it took them to answer this simple question.

On an expedition in the desert, hundreds of miles from civilization, you discover the fabled Hedron Diamond, a beautiful giant crystal worth a basketball player's ransom.

Unfortunately, the diamond is on a tiny island in the centre of a square lake.

Fortunately, you know how to swim.

Unfortunately, the lake is not water but highly concentrated acid, the result of ignoring paranoid environmentalists.

The lake's sides are 40 feet long, and shortest distance from the middle of a side to the island is a little over 19 feet.
Conveniently, close to the lake you find half-dozen wooden planks, each measuring 16 feet by 16 inches by 2 inches.
Cursing your luck you discover that they're just few feet too short to bridge the gap. If only you had brought some tools along on this expedition- rope, nails, super glue, anything! Swearing to actually plan your next expedition you sit in the dirt and try to puzzle your way out of another fine mess.

Will you walk back to civilization empty-handed? Alternatively, can you think of a way to the Hedron

But earlier you said that the firing order would be "to compensate for the obvious inequities in their marksmanship skills."

The question still holds.

And another question that I think I really have to ask is -- did you actually mean 30% rather than 1/3rd of the time?

Please, I wanna work on one riddle at a time. I really would appreciate a direct response.

Diamond. If he puts one plank across rhe corner and the second plank from the centre of that he can get the diamond with dry feet.

The dueling one is easy. Bob has the best chance of survival.
49% chance if all play fair.
If Alex tries to be tricky about it then Bob's chances go up to 70%

Not true. That will still leave you about 3 feet short.
You need all 6 planks to do it.

If he puts one white ball in one urn and all of the other balls in the other urn; then if the executioner picks the one ball urn the prisoner wins.
If the executioner picks the ninety nine ball urn the prisoner has a 49 in 99 chance of winning. So he has - approximately - a 75% chance of winning

Actually scrub what I said before, I think you can do it with 5 planks but I don't have a calculator with trig' functions so I'm not sure.

1 plank across a corner.
2 planks from the middle of the first back to the edge on each side.
1 plank across the last two.
1 plank from the middle of the last to the island.

As I said without doing the trig' I'm not sure.
I like these last ones. Geometry and probability were the only bits of maths that I ever liked.

Adrian

You are of course right. I have spilled coffee into my calculator so now I am working with pencil and that does not have the same accuracy.

But it seems to me I was on the right track. If a plank is put across the corrner and then a further two planks are placed to reach from the centre of the first plank to the edge and a plank placed across those, a plank fron the centre of that one should - I no longer trust my pencil - should now reach the centre as the first was only around 2.25 feet short (as you pointed out. Hard to say for sure as the size of the island has to be assumed), That uses five planks

Adrian

My alpologies. I must have been writing that last one while you were posting yours. As I said, I have screwed up my calculator, but the result of putting those two further planks from the centre of the first plank to the edge cuts it so fine that it is going to be very close even if it can be done.

I'm new to this puzzling and I wonder if anyone cane tell me if an answer would be acceptible as a solution to this problem if all of the planks had a mere millimetre - or less - supporting them.

Anpother query: is it permissible to calculare the density of the wood because with six planks and maybe only a fraction short, could a plank be laid from the corner to where Adrian's final board is placed? If it only needs a couple of inches and the board was allowed to protrude that much, the leverage (i.e.mechanical advantage) could well be such that the remainder of the board could easily counterbalance your weight, especially considering that your weight would be shared between that board and the island.

These planks are heavy solid planks. They measure 16 ft by 16 ins by 2 ins. Wood, on average, weighs around 30 lbs per cubic foot. That gives over one hundred pounds per plank. If one plank is put across the corner, a second plank is placed to run from the corner - on land - over the centre of the 'crossplank' and half of it sticking out over the water with it just balanced; if now three of the planks are stacked across the 'on land' end, this will be a sufficient counter balance to push the remaining plank out over the pivot plank until the end of it is over the island, and with you at three foot (see Adrian's post) beyond the cross plank. If the plank does not reach the land when set up, this does not matter. The counterbalance planks would merely be laid across the corner with the end of pivot plank beneath them

To check the figures at this point, and bearing in mind that the 'pivot' plank acts as a lever with the cross plank as the fulcrum; the pivot plank was balanced, so it takes no part in the calculation. The plank that you have just pushed out is exactly balanced by one of the counterweight planks. The two 'unaccounted for' planks have their sum of 200 lbs at a distance of 8 ft from the fulcrum and your 200 lbs (We will assume for now that you weigh two hundred pounds) your weight is 3 ft from the fulcrum, so the counterweight has a mechanical advantage of 8:3, and you would need to weigh 533 1/3 lbs before it would tip. (Had you been any weight more than 533 1/3 lbs. this idea would not work without some adjustment of the amount that sticks out over the water, but what would a 533 lb guy be doing in this jungle, or whatever it was, anyway?) So you are entirely safe so far.

If you now edge out along the planks towards the island there will come a point where the pivot tips and the extended plank touches the island. If we continue the assumption that your weight is the same as two planks, it will tilt when you reach the end of the pivot plank. With the island taking half of the weight it will tilt no further. You can now walk along the planks to the island, collect the diamond, and retreat.

Note: there is room for this method to be finessed to make it safer and more sure - with huge diamonds and lakes of acid involved this would certainly be advisable - but the principle would remain the same

Quote, Adrian

1 plank across a corner.
2 planks from the middle of the first back to the edge on each side.
1 plank across the last two.
1 plank from the middle of the last to the island.

Full answer. Well, one plank alone is not going to do it; the plank is more than three feet too short. However, what about two? If one plank is laid diagonally across the corner of the lake, you have, in effect, moved part of the shore closer to the centre. Is it enough?

Let's see... the lake's diagonal is a little over 56 feet, so the distance from one corner to the island is going to be about 28 feet. If the plank lay in the corner just barely touches land at both ends, forming a right isosceles triangle, with the plank as the hypotenuse. The center of the hypotenuse is therefore eight feet from the corner of the lake. Moreover, unfortunately, twenty feet from the island. Ouch, we are no closer than when we started!

Nevertheless, by laying down the plank across the corner we have "shaved off" the corner of the square making it "rounder". What if we continued?

Laying two more planks over the obtuse angles created between the hypotenuse and the longer sections of the shore (this sounds confusing; it's obvious if you draw it out, two new "shores" are created. A third plank connecting these two (parallel to the first) reduces the shortest distance to the island to under 16 feet. Moreover, you are there!

You get the diamond.

Quote, Lacomus

If he puts one white ball in one urn and all of the other balls in the other urn; then if the executioner picks the one ball urn the prisoner wins.
If the executioner picks the ninety nine ball urn the prisoner has a 49 in 99 chance of winning. So he has - approximately - a 75% chance of winning

Exactly right.

Quote, Adrian

The dueling one is easy. Bob has the best chance of survival.
49% chance if all play fair.
If Alex tries to be tricky about it then Bob's chances go up to 70%.

Coming from the land of Ned Kelly, who also knew a bit about shooting.
Adrian is, as always correct. (Although I am not sure about the final curtain riddle)

Full answer. Intuition tells us that Bob, the perfect shot must have the best chance at survival. However, what are his chances?

Alex and Chris will never fire at each other as long as Bob is alive- if they were to ever to kill the other, Bob would have the next shot and kill the survivor. Assume then that Alex and Chris fire all their shots at Bob. Assume as well that Bob, to maximize his chances of survival, finishes off Chris then Alex (Chris being the more dangerous opponent). That means Alex will have two shots at Bob, and Chris will have none (having died of lead poisoning by the time his turn rolls around).
Under these conditions, Bob has a 49% chance of survival. Pretty good.

So what are the odds for the other two?
If Alex makes his first shot, it becomes a simple showdown with Chris starting. In this case Alex's chance of survival is 3/13 (the sum of the infinite series of probabilities), or about 23%. However, if Alex misses, his probability of killing Bob on his next shot, or 30%.

This draws our attention to an interesting note- Alex's chances improve if he misses Bob on his first shot. Alex therefore should deliberately miss on his first shot. This raises Bob's chances to a whooping 70%, at the expense of any chance of Chris surviving. Not very nice to Chris, but if Alex really liked Chris in the first place, he wouldn't be trying to kill him.

So Bob really does have the best chance to survive, and his chances are even better than they first appeared!

Now for a change of pace;

This is a story about a girl.

While at the funeral of her own mother, she met a guy whom she did not know. She thought this guy was amazing, so much the dream guy that she was searching for that she fell in love with him immediately.

However, she never asked for his name or number and afterward could not find anyone who knew who he was.

A few days later, the girl killed her own sister.

Question: Why did she kill her sister


This riddle must be done IN YOUR HEAD and NOT using paper and a pen. Try it!

Take 1000 and add 40 to it. Now add another 1000.
Now add 30. And another 1000.
Now add 20. Now add another 1000. Now add 10.

What is the total Post it up.


As far as I know. It was Edgar Allen Poe.
Who said, "art sure no craven, Ghastly grim…"
Let me see, then, what threat is,
and this mystery explore -

We live not on land, or sea.
We have two eyes, but cannot see.
The closer you are, the more you can reflect,
on whether, your answer can be correct.
But, in the end only lies.

We are

She killed her sister because she was next on the list... then her father...

The answer is obviously 5000.

The last one looks scary in the morning.

She was hoping the dream boat would attend the sister's funeral also.


4100.

Oh! Joy knows no bounds. Adrian, you are human after all. 5000
I can now die happy. See Frank's answer.

Try, I'm gonna have to start using smileys I think. You never seem to get my sarcasm. :wink:

What about the last one. Is it a your reflection in a mirror? Oh I mean

Sarcasm is a form of irony that is widely used in English especially when people are being humorous. Generally, the sarcastic speaker or writer means the exact opposite of the word they use, often intending to be rude or to laugh at the person the words are addressed to.
I resemble that remark.

Sarcasm is when you wake up screaming & you realize you have not fallen asleep yet.

I started out with nothing & still have most of it left. Errors have been made. Others will be blamed. Macho Law prohibits me from admitting I am wrong. I plead contemporary insanity. :wink:

A young man studying logic in college was on a date with a pretty young woman. She was tweaking him about his area of study -- playing devil's advocate about the value of his field of study in "everyday life."

He told her he thought he could give her experiential appreciation for the value of the subject -- if she would agree to a couple of ground rules.

"Let's hear the rules first," she said -- concerned about the kind of trouble making a "commitment in the dark" might bring.

"I will make a statement," he said, "...you must promise that if the statment is true...you will give me a picture of yourself."

"A picture of my own choosing?" she asked warily.

"Yep," he said, "you choose the picture. Oh, and one more thing. If the statement is false -- you must promise not to give me a picture of yourself."

"Will you commit to that?", he asked.

"Sure," she said. "I'm committed to it."

So the young man made his statement -- and after thinking about it for a while, the young lady realized (to her secret amusement) that in order to keep her word, she would NOT have to give him her picture -- but instead, would have to give him a big hug and a kiss.


So -- what was his statement?

Try

My cantilever method of getting the diamond would work. Bearing in mind that it does not require the boards to be supported over an acid bath by the smallest amount of the end of the board, I suggest that it also has the greater chance oif a non-lethal outcome.