To find the probability of rolling two number cubes (dice) and getting a sum of 6 or 11, we need to first determine the number of ways to roll a sum of 6 and a sum of 11.
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Calculate the number of favorable outcomes for each sum:
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Sum of 6: The combinations are:
- (1, 5)
- (2, 4)
- (3, 3)
- (4, 2)
- (5, 1)
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So there are 5 combinations that yield a sum of 6.
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Sum of 11: The combinations are:
- (5, 6)
- (6, 5)
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So there are 2 combinations that yield a sum of 11.
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Total outcomes when rolling two dice: There are a total of \(6 \times 6 = 36\) outcomes when rolling two six-sided dice.
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Calculate the probabilities:
- Probability of rolling a sum of 6: \( \frac{5}{36} \)
- Probability of rolling a sum of 11: \( \frac{2}{36} \)
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Combine the probabilities: To find the probability of rolling a sum of 6 or 11, you add the two probabilities: \[ P(\text{sum of 6 or 11}) = P(\text{sum of 6}) + P(\text{sum of 11}) = \frac{5}{36} + \frac{2}{36} = \frac{7}{36} \]
Given the options in your question, the correct calculation is: \[ \frac{5}{36} + \frac{2}{36} \]
Thus, the correct response is: Start Fraction 5 over 36 End Fraction plus Start Fraction 2 over 36 End Fraction.