The number of 4 letter words (with or without meaning) that can be formed from the eleven letters of the…

The number of 4 letter words (with or without meaning) that can be formed from the eleven letters of the word EXAMINATION is

Solution

EXAMINATION
2N,2A,2I,E,X,M,T,O
Case I: All are different, so 8P4=8!4!=8·7·6·5=1680
Case II: 2 same and 2 different, so 3C1C274!2!=3·21·12=756
Case III: 2 same and 2 same, so 3C24!2!2!=3·6=18
Total number of words=1680+756+18=2454

Asked in: JEE Main 2020 (08 Jan Shift 2)

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