finite math
posted by yvonne .
A tray contains 14 chocolate chip cookies and 16 oatmeal raisin cookies. How many ways can a child select 4 cookies that include at least 1 chocolate chip cookie?

Chocolate cookie  C
Oatmeal cookie O
If the chocolate cookies are the same and the oatmeal cookies are the same ...
there are only the following selections
COOO
CCOO
CCCO
CCCC
If the cookies are different:
1C,3O  C(14,1)xC(16,3) = 7840
2C,2O  C(14,2)xC(16,2) = 10920
3C,1O  C(13,3)xC(16,1) = 4576
4C C(13,4)xC(16,0) = 715
for a total of 24051 
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