Two fair six-sided dice are rolled simultaneously. What is the probability that the sum of the numbers rolled is at least 10?

Answer and explanation

Correct answer: A. 1/6 (or 6/36)

  1. Step 1: Total possible outcomes when rolling two dice = 6 * 6 = 36 equiprobable outcomes.
  2. Step 2: We seek the outcomes where Sum >= 10:
  3. Step 3: Sum = 10: (4, 6), (5, 5), (6, 4) -> 3 outcomes.
  4. Step 4: Sum = 11: (5, 6), (6, 5) -> 2 outcomes.
  5. Step 5: Sum = 12: (6, 6) -> 1 outcome.
  6. Step 6: Total favorable outcomes = 3 + 2 + 1 = 6 outcomes.
  7. Step 7: Probability = 6 / 36 = 1 / 6.
Answer
1/6 (or 6/36).
Why not the others: '1/12 (or 3/36)' counts only sum = 10; '5/36' misses one combination; '7/36' includes sum = 9 incorrectly.

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