When do we have to consider Project Manager to determine Number of Communication Channels

Working through some mockup tests, i have observed that in certain cases, you simply use n(n-1)/2 formula if 9 people are given and get the right result. Whereas in certain cases, the correct answer is add Project manager, so 9 becomes 10 and then use the formula


 


When to add PM, when not to add PM?

 We need to understand the question to come up for the value of n. for example if I say in a van there are 4 people and want to get the channels then ..n here is 4. But if we ask there are 6 passenger and 1 driver ...then my n will be 7 here. So we need to understand the question.. Hope this will help.

 In the questions, they are writing 

There are 5 team members 

 

Or

7 Stakeholders

Does Pm count in this case or we have  to add the PM.

 

 Hi in my exam I did not got any confusion question like this.. they were clear. For example you are five members and 2 new joins... So this time n=7. So all depends on question. If you have a complete question pls post and then let struggle with that question to get the answer.