Difficulty: Easy
Correct Answer: 60
Explanation:
Introduction / Context:BANANA contains repeated letters, so we count distinct permutations by dividing total factorial by repeated-letter factorials.
Given Data / Assumptions:Letters: A×3, N×2, B×1; total letters = 6.
Concept / Approach:Distinct permutations = 6! / (3! * 2!).
Step-by-Step Solution:
6! = 720Divide by 3! = 6 ⇒ 120Divide by 2! = 2 ⇒ 60Verification / Alternative check:Sanity check with smaller multisets (e.g., AAB) supports the approach.
Why Other Options Are Wrong:270, 120, 360 are not equal to 6!/(3!*2!).
Common Pitfalls:Missing one of the repeated-letter divisors.
Final Answer:60
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