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Suppose I have 6 dice. One 20-sided die, one 12-sided, one 10-sided, one 8-sided, one 6-sided, and one 4-sided. The dice are in a bag and you pick two of them at random (each of them equally likely to be picked) and roll them. The first questions is what is the sample size of that experiment. The second question is what is the probability that the sum of the two dice is even? And lastly what is the probability that you roll an 8 or higher on both die.

For the first question I believe there should $20\cdot 12\cdot 10\cdot 8\cdot 6\cdot 4\cdot 30$ total outcomes. The $30$ in the last part being there to account for order, $6$ ways to choose the first $5$ for the second dice.

For the second question, would it be possible to say that since there are $31$ different sum totals, and that $16$ of those are even the probability would be $\frac{16}{31}$?

For the third question, would the number of ways of rolling an 8 or higher on both be $13\cdot 5\cdot 3 \cdot 30$? Then the probability would be that over the value in question 1?

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    Do you mean sample space? Have you tried drawing a probability tree?2012-02-22
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    "what is the sample size of that experiment" - do you mean to simply record the sum of their faces, as in $12$? Do you mean to keep track of what pairs of numbers lead to that sum, as in $(10,2)\neq(4,8)$? Or do you mean to keep track of everything, as in $(10_{20},2_8)\neq(10_{20},2_4)$?2012-02-22

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