Question 171193This question is from textbook
: A club consists of 10 members. In how many different ways can a group of 3 people be selected to go on a European trip?
I came up with the answer of 9
Is that correct?
This question is from textbook
Answer by Alan3354(69443)   (Show Source):
You can put this solution on YOUR website! A club consists of 10 members. In how many different ways can a group of 3 people be selected to go on a European trip?
I came up with the answer of 9
Is that correct?
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How did you get 9?
To pick the 1st person, there are 10 to choose from.
For the 2nd, there are 9, and 8 for the 3rd.
That's 10*9*8 = 720 possibilities.
But, since a person could be chosen 1, 2 or 3rd to form the same group, that is,
ABC is the same as BCA and BAC, you have to divide by 3*2*1 = 6.
So the # of different groups is 720/6 = 120.
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