Division
The fallacy of division is when you say that because the whole group is a certain way, every single member must be that way. Group-level facts (averages, totals, trends) don't automatically apply to each individual. Some members might be above or below the average, or the group property might emerge from the mix rather than from each part.
Examples
The class did really well. So every kid in the class did really well.
The team has a strong attack, so every forward is a star.
Household debt is high in that region, so every household there is in debt.
The department is efficient, so every employee is efficient.