SOLUTION: a person has 12 friend of whom 8 are relative.in how many ways can he invit 7 friends such that at least 5 of them may be relatives?

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Question 1135364: a person has 12 friend of whom 8 are relative.in how many ways can he invit 7 friends such that at least 5 of them may be relatives?
Answer by greenestamps(13200) About Me  (Show Source):
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(1) 5 relatives and 2 others: (8 choose 5) times (4 choose 2) -- C(8,5)*C(4,2)

or

(2) 6 relatives and 1 other: (8 choose 6) times (4 choose 1) -- C(8,6)*C(4,1)

or

(3) 7 relatives and 0 others: (8 choose 7) times (4 choose 0) -- C(8,7)*C(4,0)

Add the three numbers.