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unsure how to do perm and comb questions (1 Viewer)

bertberk

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1.There are 8 green cards, 8 red cards and 8 yellow cards. Find the probability that at least 2 green cards are chosen.
2. A committee of four is to be formed from 5 men and 4 women. In how many ways can the committee be chosen if it contains at least 2 women?

Thanks
 

pikachu975

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1.There are 8 green cards, 8 red cards and 8 yellow cards. Find the probability that at least 2 green cards are chosen.
2. A committee of four is to be formed from 5 men and 4 women. In how many ways can the committee be chosen if it contains at least 2 women?

Thanks
For the first one, how many cards are they choosing?

2) Well you can use cases:
2W2M, 3W1M, 4W

= (4C2x5C2)+(4C3x5C1)+(4C4)
= 81
 

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