Question 181521
four acts are scheduled to preform in a variety show. how many different ways are there to schedule their sappearances? 
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4 ways to choose the opening act
3 ways to choose the 2nd act
2 ways to choose the 3rd act
1 way to choose the last act.
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@ of arrangement 4P4 = 4!/(4-4)! = 4!/ 1 = 4!= 24
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Cheers,
Stan H.