How many words (with or without dictionary meaning) can be made from the letters in the word MONDAY, assuming that no letter is repeated , if 4 letters are used at a time? All letters are used at a time? All letters are used but first is vowel?

Explanation

The total no. of letters in the word MONDAY = `6` = n.


We know that the number of ways of selecting and arranging r different things from n different things is a permutation and we calculate it using the`(n_(P_r))` formula.


(i) Number of `4`-letter words that can be formed from the letters of the word MONDAY, without repetition of letters

= `6_(P_4)`

=`720/2`


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