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one of my friend asked me this question
there are infinite numbers of ball of three kind i.e. ball A,B,C. I mean there are infinite number of ball of kind A and infinite number of ball of kind B an so on.the problem is that one have to select 10 balls out of these balls,in how many "ways" he can do this? my approach for this problem was:
i can select first ball in 3 ways (A,B,C) and second ball in three ways and so on.I have 3 choices for every ball i am selecting.so 3*3*3*3*3*3*3*3*3*3 total number of ways of doing it. but my friend argues that selecting (A,B,A,B,A,B,A,B,A,B) AND (B,A,B,A,B,A,B,A,B,A) should be counted once and similar for other sets of balls. but as question says i have to find number of "WAYS" of doing it,so both the cases are different. as i should focus on "how" to select not "what" to select to find the number of "ways". please correct me if i am wrong.thanks a lot for paying attention on this problem of mine.