Suppose there are TWO locations for lunches: One in a higher-income area, and the other in a lower-income area.

A: Fixed Expense = $5,000. Revenue/unit=$15. Cost/unit=$5

B: Fixed Expense = $6,000. Revenue/unit=$13. Cost/unit=$5

Compute breakeven quantity separately for A and B. [Post calculations and your answer]

Combine A and B to compute combined breakeven. [Post calculations and your answer]

Does it look like B is getting a subsidy from A? Is there a different word to use other than 'subsidy'?

What other 'broader' costs and revenues might be included to reflect the true impact of school/day-care meals? For example, if these were for elder care, you might add expected savings from reduced falls (because fewer people hungry to the point of hypoglycemia).