Sarthaks Test
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in Mathematics by (70.5k points)

Ten different letters of english alphabet are given. Out of these letters, words of 5 letters are formed. How many words are formed when at least one letter is repeated ?

(a) 69760 

(b) 98748 

(c) 96747 

(d) 97147

1 Answer

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Best answer

Correct option: (a) 69760


Number of required words

= Total words - number of words with no. letter being repeated

= 105 - 10P5 = 69,760

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