Two fair dice are thrown. What is the probability that the sum of the numbers is ?
Answer and explanation
Correct answer: A. 1/6
- Step 1: When two fair six-sided dice are thrown, the total number of equally likely outcomes in the sample space is .
- Step 2: Identify the ordered pairs whose sum equals : (1, 6), (2, 5), (3, 4), (4, 3), (5, 2), (6, 1), giving favorable combinations.
- Step 3: The probability is the ratio of favorable outcomes to total outcomes: .
Answer
1/6.
Why not the others: 1/36 assumes only a single outcome yields the required dice sum; 7/36 is an incorrect dice probability fraction; 1/2 is an incorrect dice probability fraction.
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