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In this question, given at a certain school, there are seven members in the student council, and four members will be selected from the group above to form an executive committee, consisting of a president, vice president, secretary and a treasurer.
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Now, part one, we want to find number of ways these four positions can be filled.
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Now, first of all, take note that the four person chosen will be without replacement.
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For part one, after these four people are chosen, they can be slotted into four different positions or titles.
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So there will be arrangements to these four persons as you arrange them within the four titles here.
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So the order is important because there will be arrangements.
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Now without replacement order is important, we will be using permutation.
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And that's the one with p.
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So number of ways these four positions can be filled will be from the seven members you permuted four.
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Now, if you do not understand this, it's equivalent to from these seven members, we choose for n.
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Now, n in probability is thumps or is plus...