Answer:
90
Step-by-step explanation:
A group of 10 people is choose a chairperson and vice-chairperson. They put all 10 peoples names into a bar. The first name drawn becomes chair. The second name drawn becomes vice-chair. How many possible combinations of chair and Vice-chair are there ?
This is calculated using the Permutation formula
nPr = n!/(n - r)!
Where:
n = 10 people
r = 2 = 2 positions to be filled , Chairman and Vice chairman
Hence:
10P2 = 10!/(10 - 2)!
= 90 ways
