JEE Mains · Maths · STD 11 - 6. permutation and combination
The number of 4-letter words, with or without meaning, which can be formed using the letters of 'PQRPQRSTUVP', is:
- A 1420
- B 1422
- C 1424
- D 1426
Answer & Solution
Correct Answer
(B) 1422
Step-by-step Solution
Detailed explanation
\(P \rightarrow 3, Q \rightarrow 2, R \rightarrow 2, \quad S, T , U , V\) Case I 3 alike, 1 different \({ }^1 C _1 \times{ }^6 C _1 \times \frac{4!}{3!}=24\) Case II 2 alike, 2 alike \({ }^3 C _2 \times \frac{4!}{2!2!}=18\) Case III 2 alike, 2 different…
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