There are 7 performers who are to present their acts at a variety show. One of them insists on being the first act of the evening. If this request is granted, how many different ways are there to schedule the appearances?

Respuesta :

For the first performer, there is only one choice
for the second, 6 choices
third, 5
fourth,4.....

You have to multiple them together :
1*6*5*4*3*2*1=720ways

there are 720 ways to schedule this show