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A pair of standard since dice are rolled. Find the probability of rolling a sum of 9 with these dice.

P(D1 + D2 = 9) = ---

User JoeyC
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1 Answer

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The total number of possible outcomes when rolling two standard six-sided dice is 6 x 6 = 36. To find the number of outcomes that result in a sum of 9, we can create a table to visualize all of the possible outcomes:

| Die 1 | Die 2 | Sum |
|:------:|:------:|:------:|
| 3 | 6 | 9 |
| 4 | 5 | 9 |
| 5 | 4 | 9 |
| 6 | 3 | 9 |

From this table, we can see that there are four possible outcomes that would result in a sum of 9. Therefore, the probability of rolling a sum of 9 with two standard six-sided dice is:

P(D1 + D2 = 9) = number of outcomes that result in a sum of 9 / total number of possible outcomes
P(D1 + D2 = 9) = 4 / 36
P(D1 + D2 = 9) = 1 / 9

So the probability of rolling a sum of 9 with two standard six-sided dice is 1/9.
User Mjtamlyn
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