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Find the number of permutations of letters in each of the following words.(i) DIVYA(ii) SHANTARAM(iii) REPRESENT(iv) COMBINE(v) BAL BHARATI |
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Answer» (i) There are 5 distinct letters in the word DIVYA. ∴ Number of permutations of the letters of the word DIVYA = 5! = 120 (ii) There are 9 letters in the word SHANTARAM in which ‘A’ is repeated 3 times. ∴ Number of permutations of the letters of the word SHANTARAM = \(\frac{9!}{3!}\) = 9 x 8 x 7 x 6 x 5 x 4 = 60480 (iii) There are 9 letters in the word REPRESENT in which ‘E’ is repeated 3 times and ‘R’ is repeated 2 times. ∴ Number of permutations of the letters of the word REPRESENT = \(\frac{9!}{3!2!}\) = \(\frac{9\times8\times7\times6\times5\times4}2\) = 30240 (iv) There are 7 distinct letters in the word COMBINE. ∴ Number of permutations of the letters of the word COMBINE = 7! = 5040 (v) There are 10 letters in the word BALBHARATI in which ‘B’ is repeated 2 times and ‘A’ is repeated 3 times. ∴ Number of permutations of the letters of the word BALBHARATI = \(\frac{10!}{2!3!}\) \(=\frac{10\times9\times8\times7\times6\times5\times4\times3\times2\times1}{2\times3\times2}\) = 302400 |
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