Ans:(n+2)2n-1
Find the number of selections of n things from three piles,one consisting of n identical things of one type,second consisting of n identical things of second type and third consisting of n different things .
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4 Answers
Lokesh Verma
·2009-10-09 23:53:25
hmm.. i din see taht the 3rd one has different objects
Take teh cases for the number of objects of type one, then of type 2 and then multiply by the number of ways you can chose the rest..
take the summation (A binomial..)
And read my comment on one of your other posts.