Two fair six-sided dice are rolled together. What is the probability that the two numbers add up to 7?
Answer and explanation
Correct answer: A. 1/6
- Step 1: There are 6 x 6 = 36 equally likely outcomes.
- Step 2: The pairs that make 7 are (1,6), (2,5), (3,4), (4,3), (5,2), (6,1), which is 6 outcomes.
- Step 3: 6/36 = 1/6.
Answer
1/6.
Why not the others: 1/12 counts only half of the pairs, 7/36 adds an extra pair, and 1/3 is double the true chance.
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