
Check weighted average calculations before combining group results
To find the average page count across two collections of books, add their total pages and divide by their combined number of books. When you have each collection's mean instead of its total, multiply that mean by the number of books it describes. The counts matter: a collection of eight books contributes more observations than a collection of two. Simply averaging their reported means gives both collections equal influence, which answers a different question. For weighted average calculations , verify each step.










