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A Tuesday Puzzle

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A Tuesday Puzzle

#1

A Tuesday Puzzle

Dan Donaldson

Here is one for you:

You have 4 dice with the following numbers on them:

3,3,3,3,3,3

2,2,2,2,6,6

1,1,1,5,5,5

4,4,4,4,0,0

your challenges is to choose one of the dice, and then I will take another. We will roll our dice together, trying to get the highest roll, and the winner is the one who rolls the best out of ten. Which die should you choose?

Re: A Tuesday Puzzle

#2

Re: A Tuesday Puzzle

John Veerkamp

222266

Re: A Tuesday Puzzle

#3

Re: A Tuesday Puzzle

Dan Donaldson

maybe, but maybe not. What is your rationale?

Re: A Tuesday Puzzle

#4

Re: A Tuesday Puzzle

Alex Y

Any of them. You'll only win 1/3 of the time w/ a good opponent.

Re: A Tuesday Puzzle

#5

;(

Dan Donaldson

Statistically, with two of the dice, I can pick one to win best out of ten consistently. Which one is the "best"?

Re: A Tuesday Puzzle

#6

Actually, I can pick one that will beat you.

Dan Donaldson

There is a hint buried in this answer

Re: A Tuesday Puzzle

#7

Re: ;(

Larry Barrett

I think 2 is "best" in sense of having highest probability of winning against the other die. But Alex is correct in saying that for any die that you pick, I can select one that has a probability = 2/3 of winning against you on one roll of the dice.

1 wins against 2 with Prob=2/3, against 3 with P=1/2, against 4 with P=1/3

2 wins against 1 with P=1/3, against 3 with P=2/3, against 4 with P=5/9

3 wins against 1 with P=1/2, against 2 with P=1/3, against 4 with P=2/3

4 wins against 1 with P=2/3, against 2 with P=4/9, against 3 with P=1/3

Re: A Tuesday Puzzle

#8

Those are the probs I got as well

Alex Y

And since the second person gets to pick another die (as I read the puzzle, at least), I'll stick with my "it doesn't matter" answer. I agree that if the second person takes another die at random, 2 is the best die to start with, giving you slightly better than 50-50 odds, 14/27 chance of winning if I calculated correctly.

Re: A Tuesday Puzzle

#10

Re: Those are the probs I got as well

Dan Donaldson

Sorry Alex, I misread your answer. You are correct. This is kind of a trick question kind of like the rock, paper , scissors game. For any choice, there is another choice with a higher probability.

Re: A Tuesday Puzzle

#11

Re: Those are the probs I got as well

Alex Y

No problem. My answer was rather cryptic, as I was trying to type it out fast on my phone before having to turn it off for a red-eye flight.

This is interesting, taking me back to sophomore abstract algebra. You expect a relationship like "is more probable than" to be transitive, but the relationship here is not transitive.

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