A fair six-sided die is rolled twice. What is the probability that the sum of the two rolls is 7?
Answer and explanation
Correct answer: B. 1/6
- Step 1: There are 36 equally likely outcomes. Step 2. Six of them sum to 7: (1,6), (2,5), (3,4), (4,3), (5,2), (6,1). Step 3. 6/36 = 1/6. Answer: 1/6. Why not the others: Rolling doubles on two independent fair dice has 6 favorable outcomes out of 36 possible ordered pairs, simplifying to 6/36 or exactly 1/6.
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