Ten different letters of alphabet are given, words with 5 letters are formed from these given letters. Then, the number of words which have at least one letter repeated is:
Ten different letters of alphabet are given, words with 5 letters are formed from these given letters. Then, the number of words which have at least one letter repeated is: Correct Answer 69760
Number of words which have at least one letter replaced,= Total number of words - total number of words in which no letter is repeated.= 105 – 16P5= 100000 − 30240= 69760