Statistics Expected Variable Question

AI Thread Summary
To calculate the expected value E(Y) when two fair dice are thrown, Y represents the larger score of the two dice. There are 36 possible outcomes when rolling two dice, and for each outcome, the larger number needs to be identified. The expected value can be found by summing the larger numbers from all pairs and dividing by 36. It is important to note that in cases where both dice show the same number, either number can be considered as the larger one. This approach will yield the correct expected value for Y.
thomas49th
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Homework Statement


Y is the larger score showing when two dice are thrown
Calculate E(Y)


Homework Equations


Presume the dice are fair


The Attempt at a Solution



Hmm not sure. I've listed combinations of throw events on paper but I don't think that will help. Y can never be 1. Y can never be the same as the other die?
Do I want to draw a probability distrubution table?

I've been messing around with it for a while with not much progress

Thanks :)
 
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If both dice come up with 1s, if you don't count the 1, you won't have anything to count for that roll.

With two dice, there are 36 possible outcomes: {(1, 1), (1, 2), ... , (1, 6), (2, 1), ... (2, 6), (3, 1), ..., (3, 6), (4, 1), ..., (4, 6), (5, 1), ..., (5, 6), (6, 1), ..., (6, 6)}.

I think that for the expected value of Y, E(Y), you add together the larger number in all 36 pairs, and divide by the number of pairs, which is 36. For the 6 pairs that have the same value, pick either number to be the larger; it's certainly not the smaller of the two.
 
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