To find the probability of rolling two number cubes (d6 dice) and getting a sum of 6 or 11, we first determine the number of combinations that yield each sum.
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For a sum of 6, the possible combinations are:
- (1, 5)
- (2, 4)
- (3, 3)
- (4, 2)
- (5, 1) This gives us 5 combinations.
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For a sum of 11, the possible combinations are:
- (5, 6)
- (6, 5) This gives us 2 combinations.
Now, we can add the number of combinations for both sums:
- Total combinations = 5 (for 6) + 2 (for 11) = 7 combinations.
The total number of possible outcomes when rolling two dice is \(6 \times 6 = 36\).
Thus, the probability of rolling a sum of 6 or 11 is: \[ \frac{7}{36} \]
Looking at the responses:
- \( \frac{5}{36} + \frac{2}{36} \)
- \( \frac{6}{36} \cdot \frac{2}{36} \)
- \( \frac{5}{36} \cdot \frac{2}{36} \)
- \( \frac{6}{36} + \frac{2}{36} \)
The correct response for calculating the probability of a sum of 6 or 11 is:
- \( \frac{5}{36} + \frac{2}{36} \), which combines the probabilities of both sums.
So, the correct choice is: Start Fraction 5 over 36 End Fraction plus Start Fraction 2 over 36 End Fraction.