Difficulty: Easy
Correct Answer: 2520
Explanation:
Introduction / Context:Again a multiset permutation: 7 letters with a duplication of N. The standard formula applies.
Given Data / Assumptions:
Concept / Approach:7! / 2! counts distinct arrangements since interchanging the two N’s does not create a new word.
Step-by-Step Solution:
7! / 2! = 5040 / 2 = 2520.Verification / Alternative check:Check multiplicities: only N repeats; no other repeated letters.
Why Other Options Are Wrong:5040 ignores repetition; 1260 or 840 divide by too much.
Common Pitfalls:Misidentifying repeat counts in the word.
Final Answer:2520
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