# Try out the ODDBALL logic test?

Discussion in 'Intelligence & Machines' started by Alan McDougall, Jul 15, 2010.

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1. ### MaikaRegistered Member

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86

a fat kid lol. that's funny.

i consider a pan scale a see saw.

i dunno what your last sentence means. you have three weighings how do you get more?

3. ### StryderKeeper of "good" ideas.Valued Senior Member

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In some attempts people had alternatives (Non working ones I might add),

In instance if you weigh 5 and 5 and create an if statement.

If they are equal then somewhere in the other two is the odd one out, swap 1 of the 5 with one of the 2 and weigh it, If it's heavier/lighter then you've found the outcome, if not weigh the otherone.

If when weighing 5:5 is unequal.... etc.

You end up equating multiple IF's that equal a greater number of weighings.

5. ### John99BannedBanned

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I think you realized that it is impossible without marking the balls because the op clearly states the ball are IDENTICAL (except for weight). Also, how do write in steel balls with chalk? Unless the stell is rusted i dont think you can.

How much of a weight difference are we talking about?

I would bet that anyone contemplating this test is thinking of the shiny steel balls. I would like to see you write on those with chalk.

http://bit.ly/96mxL2

Last edited: Aug 6, 2010

7. ### DywyddyrPenguinaciously duckalicious.Valued Senior Member

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18,951
Wrong. It's not particularly easy, but it's possible. Oh, and the wording would be write on steel balls. Not "in".
But then again, anyone in their right mind would use engineer's blue rather than chalk.

It's irrelevant.

And you seem to be conflating "labelling" with physically writing on the balls. That's not necessary.

Last edited: Aug 5, 2010
8. ### StryderKeeper of "good" ideas.Valued Senior Member

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Technically to put John99's mind at rest, you wouldn't even need to write on the balls. You are merely attempting to mark the positions, so you could mark it on a sheet of paper and just keep the balls in a specific order.

9. ### DywyddyrPenguinaciously duckalicious.Valued Senior Member

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Hence my last sentence in the post above yours.

A "mental label" would suffice.

10. ### John99BannedBanned

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you need to get lucky on one of the two left off the scale. Thus game of chance and not logic. Alan even claims:

12 balls and 3 weighings. The best way is to weigh 6 and six to weigh less is diminishing.

Last edited: Aug 6, 2010
11. ### John99BannedBanned

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22,046
Not feasible.

In light of this ex post facto change where the balls CAN be marked i would issue a new ball type.

I would say that the OP should contain already marked pool balls.

http://bit.ly/bn8nMZ

I doubt you can visualize the placement of the balls in a weighing scale though due to the order of the balls being out of line and circular. The reason is on ball will find the center and the other balls will congregate in a circular fashion to the center ball. this is very difficult achievement to do by eye. Good luck with that.

12. ### John99BannedBanned

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Also the reason i asked if the difference was small or large is becuase the chalk dust can throw off the ball weight.

13. ### DywyddyrPenguinaciously duckalicious.Valued Senior Member

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18,951
Stawman.
It doesn't matter about differentiating between balls on the same pan of the scales.
And Stryder's point was entirely valid.
You're missing the point completely.

14. ### John99BannedBanned

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IF one of the two left off balls is the odd ball.

15. ### DywyddyrPenguinaciously duckalicious.Valued Senior Member

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No. Regardless.
You start off with a group and check for weight variation of the group.
And use successive steps to narrow that group down to one individual ball.
They do not need to be differentiated at all while ON the pan.

16. ### John99BannedBanned

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You have 3 chances to weigh 12 balls. Have you forgotten that?

17. ### DywyddyrPenguinaciously duckalicious.Valued Senior Member

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Not at all.
That's why it's a logic problem.
Reducing the steps to a maximum of 3 and at the same time ascertain the correct ball (and variance).

18. ### John99BannedBanned

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To stryder: I wasnt being facetious with the images of the balls because i needed to illustrate that not all balls are red. (Billiard) In cas you never seen non billiard pool balls.

19. ### StryderKeeper of "good" ideas.Valued Senior Member

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John99, you know full well that this wasn't the actual solution, this was for explaining how you could end up with multiple weighings in attempting a solution.

20. ### Captain KremmenAll aboard, me Hearties!Valued Senior Member

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12,738
Consider the old nursery rhyme:

See, saw, Marjorie Daw,
Jennie shall have a new master.
She shall have but a penny a day,
because she can't work any faster.

Pan Scale, Marjorie Daw,
Jennie shall have a new master.
She shall have but a penny a day,
because she can't work any faster.

As regards writing on the balls.
All you have to do is use the same amount of ink each time for each number.
When you wrote 12, it would need to be in smaller writing than when you wrote 1.
If you hadn't used enough ink, you could just scribble on the ball.

Last edited: Aug 6, 2010
21. ### Alan McDougallAlan McDougallRegistered Senior Member

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410
Miniscule

You don't need to write in the balls try just using a little coureled dot

22. ### MaikaRegistered Member

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86
you guys are making this too complex. i want those balls so i can try it out.

and why can't you just put the balls in different places, you don't need to mark them.

chill and have a drink.