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In the word ROOT, why are the letters not all treated as different?
ATwo letters are shortened
BTwo letters are the same
CTwo letters are silent
DTwo letters are stressed
Answer & Solution
Correct answer: B. Two letters are the same
1. Rearranging a word with repeated letters overcounts the arrangements.
2. In this case, the letters of the word are not all different.
3. There are 2 Os, which are of the same kind.
4. So the plain permutation count has to be corrected.
_Source: NCERT Class XI Mathematics, Ch 6 'Permutations and Combinations'_
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