How many words, with or without meaning can be formed from the letters of the word 'MONDAY', assuming that no letter is repeated, if (i) 4 letters are used at a time (ii) all letters are used at a time (iii) all letters are used but first letter is a vowel ?
(i) Total number of 4 letter words formed from the letters of the word 'MONDAY' is =6C4×4!=360
(ii) Totalnumber of words formed by using all letters of the word 'MONDAY' is = 6! = 720
(iii) There are two vowels A and O. So, first place can be filled in 5! ways. So, total number of words beginning with a vowel =2×5!=240