Math9-12+
Calculating Debt-to-Income Ratio Practice Set
By Brandon M.
A 10th-grade practice set that walks students through calculating debt-to-income (DTI) ratios, starting with simple division-to-percent warm-ups and moving into totaling multiple debts against monthly income. It builds proportional reasoning and personal finance literacy, and it flags a common mistake (wrongly including utilities in debt totals) to discuss.
Customize for your classroom
Teacher Guide & Tips
- Use as a 30-45 minute independent or partner practice after introducing ratios and percents, or as a finance-unit warm-up before a discussion on how lenders evaluate borrowers.
- Discussion question: Why do lenders care about DTI rather than just the size of a debt, and what might change if a borrower's income rose by $500 a month?
- Scaffold for struggling readers: Have them complete Part 1 first, then model one problem from Part 2 step by step, labeling the debt total and income before dividing.
- Extension for advanced students: Ask them to determine how much additional monthly debt a borrower could take on while staying under a 36% DTI threshold.
- Estimated time: about 30 minutes for the warm-up and totaling problems, plus 10 minutes for debrief on the utilities error.
Math9-12+
Calculating Debt-to-Income Ratio Practice Set
By Brandon M.
A 10th-grade practice set that walks students through calculating debt-to-income (DTI) ratios, starting with simple division-to-percent warm-ups and moving into totaling multiple debts against monthly income. It builds proportional reasoning and personal finance literacy, and it flags a common mistake (wrongly including utilities in debt totals) to discuss.
Customize for your classroom
Teacher Guide & Tips
- Use as a 30-45 minute independent or partner practice after introducing ratios and percents, or as a finance-unit warm-up before a discussion on how lenders evaluate borrowers.
- Discussion question: Why do lenders care about DTI rather than just the size of a debt, and what might change if a borrower's income rose by $500 a month?
- Scaffold for struggling readers: Have them complete Part 1 first, then model one problem from Part 2 step by step, labeling the debt total and income before dividing.
- Extension for advanced students: Ask them to determine how much additional monthly debt a borrower could take on while staying under a 36% DTI threshold.
- Estimated time: about 30 minutes for the warm-up and totaling problems, plus 10 minutes for debrief on the utilities error.