A fair six-sided die is rolled twice. What is the probability of rolling a sum of 8?
Answer and explanation
Correct answer: C. 5/36
- Step 1: Determine the total number of equally likely outcomes: 6 * 6 = 36.
- Step 2: Enumerate pairs (d1, d2) that sum to 8: (2,6), (3,5), (4,4), (5,3), (6,2). Total favorable outcomes = 5.
- Step 3: Probability = 5 / 36.
Answer
5/36.
Why not the others: Option 1/6 (6/36) represents a sum of 7, which has 6 pairs. Option 1/9 (4/36) represents a sum of 9. Option 7/36 counts non-existent dice faces.
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