Bunuel wrote:
A tutor is scheduling his appointments for the day and has 5 students to see: Liz, Jake, Sarah, Ramsey, and Cody. If the tutor sees all his students that day how many different schedules of students are possible?
A. 3125
B. 1554
C. 120
D. 60
E. 15
Since the tutor is planning a schedule of appointments, the order in which the students are seen matters, and thus we have a permutation.
Thus, the number of ways to schedule 5 students is 5P5 = 5!/(5-5)! = 5!/0! = 5! = 120. (Recall that 0! = 1.)
Answer:
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