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The number of 4-letter words, with or without meaning, which can be formed using the letters PQRPQRSTUVP, is .
1422
Letters: P (3), Q (2), R (2), S, T, U, V (1 each) → 7 different letters.
(i) All 4 different: 7P4 = 840
(ii) One pair + 2 different: 3C1 6C2 4!2! = 3 15 12 = 540
(iii) Two pairs: 3C2 4!2! 2! = 3 6 = 18
(iv) Three alike (P) + 1 different: 6C1 4!3! = 6 4 = 24
Total = 840 + 540 + 18 + 24 = 1422
Answer: 1422
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