Question
Eight different letters of an alphabet are given. Words of four letters from these are formed. The number of such words with at least one letter repeated is
Hint:
In the question 8 different letters are given we have to find the number of 4 letter words with at least one letter repeated this means that one letter can be repeated or two letter can be repeated or three or four but no letter repeated is not allowed. So, we will first find the total number 4 letter words formed from 8 letters then we will subtract the number of 4 letter words formed from 8 different letters with no repetition allowed.
The correct answer is:
Total number of 4 letter words formed from 8 different letters =
number of 4 letter words formed from 8 different letters with no repetition allowed =
So, the number of 4 letter words formed from 8 different letters with at least one letter being repeated =
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