Two standard dice are rolled. What is the probability that the sum of the two numbers is at least 8?
Answer
23/36
The correct answer is 23/36 — Probability = favourable/total = 23/36.
Step-by-step solution
- Total possible outcomes when rolling two dice = 6 × 6 = 36.
- Count favourable outcomes for sums 8,9,10,11,12.
- For sum 8: 5 combinations; 9: 6; 10: 5; 11: 4; 12: 3.
- Total favourable = 5+6+5+4+3 = 23.
- Probability = favourable/total = 23/36.
Common mistake: Missing a combination when counting favourable outcomes.
Concept tested: Discrete random variables – dice sum probability.
Published · How this solution was prepared and checked
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