1the no.of ways of distribuiting n identical things in r groups is n+r-1 C r-1;
hence answer has to be (15C9).(15C 9)
6 apples and 6 oranges are to be distributed among 10 boys. Find the number of ways in which this can be done .
Ans : (10+6-1 C6 )2 How can this be possible ??????????
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1How do you get it ???? applying 9 doesn't quite do the work. n+r-1Cr-1....is not working here ... how ??
62first you have to partition 6 into ten parts..
so have 9 dividers and 6 apples in a row
the number of ways is 15!/ (9! x 6!) = 15C6
same with the oranges..
hence the square.
62Hint: one divider seperates the whole thing into 2 parts...
similarly, we need 9 to seperate 6 apples in 10 parts
so you have to place 9 dividers and 6 apples in a row..
hence you have to arrange 15 objects 9 objects of one kind and 6 of another..
which i sgiven by 15!/(9! 6 !)