The number of permutations which can be formed out of the letters of the word "SERIES" talking three letters together, is:

Explanation

Given letters S,S,E,E,R,I

There are 4 district letters S,E,R,I.

We need to form 3−lettered words.

Case 1:All 3 letters are district


so,or choosing 3 letters we have =`4_(C_3)`
​
Rearrangements =`3!
`
Total =`4_(C_3) xx3!=24
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