Two fair six-sided dice are rolled simultaneously. What is the probability that the sum of the two uppermost faces equals 7?
Answer and explanation
Correct answer: B. 1/6
- Step 1: Total possible outcomes = 6 × 6 = 36. Step 2. Pairs summing to 7: (1,6), (2,5), (3,4), (4,3), (5,2), (6,1) => 6 favorable outcomes. Step 3. Probability = 6 / 36 = 1/6. Answer: 1/6. Why not the others: 1/12 corresponds to 3 outcomes; 7/36 confuses the sum with numerator; 5/36 is probability of summing to 6 or 8.
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