Two fair dice are thrown. What is the probability that the sum of the two numbers is 8?
Answer and explanation
Correct answer: D. 5/36, from the pairs (2,6), (3,5), (4,4), (5,3) and (6,2)
- Step 1: There are 6 x 6 = 36 equally likely outcomes.
- Step 2: The sum 8 occurs for (2,6), (3,5), (4,4), (5,3), (6,2): 5 outcomes, so P = 5/36.
Answer
5/36.
Why not the others: The other fractions assume equal sums, ignore ordered pairs, or drop one pair.
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