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In this question given at a certain college, the student engineers council comprises of one student representative from each of the five engineering majors.
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So the total number of students in this council is five.
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In part a, we want to find the number of ways both council president and vice president.
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So two different distinct positions can be selected.
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So take note that the two persons selected for this position is without replacement.
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And that order selection is important because there are two different positions that the two persons can be slotted into.
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So without replacement order is important, we will be using permutation.
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That is, if i have n distinct objects and i want to permutate r on them, it will be n factorial divided by n minus r factorial.
01:07
So in this case, it would be 5p2.
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And if you have a calculator, you can just use the calculator, if not just use the formula.
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So 5p2 is 20.
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Now if you do not understand 5p2 is equivalent to, from the five council members, you're going to choose two for the two positions.
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Now, n is times or is plus.
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So n will be times.
01:40
There is two factorial ways to arrange these two person in the two different positions...