A conference is to have eight presentations over the course of one day, consisting of three long ...
A conference is to have eight presentations over the course of one day, consisting of three long presentations, and five short presentations. If the conference organizer doesn't want consecutive long presentations, and the conference is to start with a short presentation, how many schedules of presentations are possible?
Answer/Solution
7200
Steps/Work
S*S*S*S*S*
5 short presentations can be arranged in 5!=120 ways.
As for 3 long presentations: each can be placed instead of any of the 5 star, so in C35=10C53=10 ways, and they also can be arranged in 3!=6 ways.
Total = 120*10*6 = 7,200
Ans:B
5 short presentations can be arranged in 5!=120 ways.
As for 3 long presentations: each can be placed instead of any of the 5 star, so in C35=10C53=10 ways, and they also can be arranged in 3!=6 ways.
Total = 120*10*6 = 7,200
Ans:B