Hello the question is above , I can't understand such type of questions, please help.
the answer is 479 but how does it come?
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As $A$ occurs $4$ times, we can choose A in $4+1$ ways
So, the number of ways of selection of no or more letters from the word: AAAABBCCCDEF will be $N=(4+1)(2+1)(3+1)(1+1)(1+1)(1+1)$
Clearly, this contains one combination of choosing no letter
So, the number of ways of selection of one or more letters will be $N-1$