If you have the following table:
Project City Invoice #trainings
A Seattle $ 500 1
A Washington $300 2
A New York $100 2
B Texas $300 3
B Orleans $250 1
I am mixing up everything; and the aswer is probably very easy... but what is the function again to get a report with the weighted average invoice of per type project and the sum of the trainings executed per project? (not the real case but same reasoning, that is why I use a simple example). The city name is thus not relevant anymore, only the type of project.