A fair die is rolled. What is the probability that the number shown is a prime number?
Answer
1/3
The correct answer is 1/3 — Hence probability = 1/3.
Step-by-step solution
- List all possible outcomes when a fair die is rolled: {1,2,3,4,5,6}. (6 outcomes)
- Identify favourable outcomes: prime numbers among these are 2,3,5. (3 favourable)
- Compute probability as favourable / total = 3/6 = 1/3.
- Hence probability = 1/3.
Common mistake: Treating 6 as prime or not simplifying fraction
Concept tested: Classical probability of a single event
Published · How this solution was prepared and checked
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