SOLUTION: A group of 3 students is to be selected from a group of 12 students to take part in a class in cell biology. a) in how many ways can this be done? b) in how many ways can the gr

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Question 163920: A group of 3 students is to be selected from a group of 12 students to take part in a class in cell biology.
a) in how many ways can this be done?
b) in how many ways can the group who will not take part be chosen?

Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
A group of 3 students is to be selected from a group of 12 students to take part in a class in cell biology.
a) in how many ways can this be done?
Ans: 12C3 = [12*11*10]/[1*2*3] = 220
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b) in how many ways can the group who will not take part be chosen?
Ans: the answer is the same because for each group that is chosen
there is a group that is not chosen.
So 12C3 = 12C9
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Cheers,
Stan H.