Question 1148118
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P(5,2) = 5*4 = 20  is the number of all <U>ORDERED</U> pairs of 5 different items.


C(5,2) = {{{(5*4)/(1*2)}}} = 10  is the number of all <U>unordered</U> pairs of 5 different items.


So, these quantities count DIFFERENT entities.


Therefore, there is nothing unexpected that they are different.
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