Math Is Fun Forum

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o binga banga bonga... I no wanna dance de conga

Yup, p, mathsy earned his point...

Ok, mathsyperson, next game coming right up! But this game is over. Your list in post #12 would have scored 0 points, because your name doesn't start with p.

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Come to think of it, you don't really need any opponents in this game, it's just as much fun without...  something like 20 Questions.

What a lot of baloney! If you have two children, and you tell me at least one is a boy, this can in no way influence what the other is. That is not only intuitive, it is obviously true. Regardless of whether the mentioned boy is one born on a Tuesday, having blue eyes, being a runt or anything else, the properties of the boy have no bearing on the fact that it is a boy.

So any reasoning to the contrary must be fallacious. In fact all Devlin's reasoning contains numerous non-sequiturs (unwarranted assumptions).

The tree is also fallacious, since it assumes cases to be equally probably which are no longer equally probable. The tree, however, does highlight the inaccuracy of the 1 in 3 assumption.

In all cases, the other child is equally likely to be boy or girl, there is no information given which can affect this.
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I posted the above before, then deleted it thinking it mistaken, so I have thought a lot before coming to the following rather earth-shaking conclusions.

The set of probabilities BB BG GB GG can only be considered valid or applicable if we have no information about the possibility of any one of these 4 possibilities. As far as we know, they are all equally possible.

The moment it is stated that one or two are boys, the applicability of the set is destroyed. We cannot simply delete the possibility GG and keep the other three, because the whole set DEPENDS on GG being a possibility.

Therefore we'll have to look at the problem afresh, and only apply probabilities to uncertain facts. We can't mix certain and uncertain data in one equation.

So we can say: there is at least one boy; that is a certainty. So we put one boy in a cage. That leaves one other child about whom we know absolutely nothing. Therefore the chances are equal that the  second child will be B or G.----------------QED.

The second problem is exactly the same: the probability that the boy was born on a Tuesday is immaterial, because it is no longer a probability but a certainty.

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The moderator was the one who introduced the concept of fractional house numbers: as far as I recall, it was you yourself. I referred to your behaviour as "a boorish lack of a cooperative spirit".

I made my point a week ago. MIF is the one who has reopened this subject after a delay of one week. If moderators step out of line, I won't hesitate to rap them over the knuckles. Just grin and bear it

I don't continue to hold any grudge against those I have already punished.

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Thanks for the suggestion, phrontister. I agree on the merit of having an easily-accessible authority.
But I do not wish my games to become a test of word knowledge, but rather a test of intuition and logic.
For that reason I would favour the smallest dictionary possible.

I would rather that players restricted their words to commonly used words. There will always be more than enough of such words to enable my games to be played properly. These games do not at all require a great vocabulary of arcane words, as scrabble does.
And I would like to keep it that way. Hoping you will understand.