Two fair six-sided dice are rolled. What is the probability that the sum of the numbers is 8?
Answer and explanation
Correct answer: C. 5/36
- Step 1: Total possible outcomes for rolling two dice: 6 * 6 = 36.
- Step 2: List pairs summing to 8: (2,6), (3,5), (4,4), (5,3), (6,2).
- Step 3: Count favorable outcomes: exactly 5 pairs.
- Step 4: Probability: P(sum = 8) = 5 / 36.
Answer
5/36.
Why not the others: '1/6' (6/36) is the probability of obtaining sum 7; '7/36' overcounts pairs; '1/9' (4/36) is the probability of sum 9.
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