Question

Our physics club has 20 members, among which we have 3 officers: President, Vice President, and Treasure. However, one member, Alex, hates another, Bob. How many ways can we fill the offices if alex refuses to serve as an oficer if alex refuses to serve as an officer if bob is also an officer

Answer 1

Answer: 6840 ways

Explanation:

Members in the club = 20

Offices available = President, Vice President, and Treasure.

Solution:

The offices can be filled in the following way if Alex refuses to serve as an office an bob is an officer. With no one holding more than one office

= 20P3

= 20*19*18

= 6840 ways.