Two fair dice are thrown. What is the probability that the sum of the numbers is ?
Answer and explanation
Correct answer: B. 5/36
- Step 1: The sample space for rolling two six-sided dice contains equiprobable outcomes with .
- Step 2: List the outcomes satisfying : (2, 6), (3, 5), (4, 4), (5, 3), (6, 2), which yields pairs.
- Step 3: Calculate the probability: .
Answer
5/36.
Why not the others: 1/6 assumes a uniform distribution over all possible sums; 5/12 is an arithmetic fraction miscalculation (); 1/36 assumes only a single outcome yields the required dice sum.
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