A comprehensive high school Business Math unit covering expense tracking, monthly averages, working backward from budget targets, income deductions, percentage-based allocations, and an applied real-world personal budgeting project.
5. The Byrley Family Q2 Groceries (Quarter = 3 Months)
The Byrley family’s Q1 average monthly grocery expense was $357.85. In Q2, they spent $383.79 in April and $341.44 in May. What is their spending limit for June to maintain that average?
1. Q2 Budget (Avg × 3)
Target = $ _____________
2. Known Sum (Apr+May)
Spent = $ ______________
3. June Limit (Subtract)
Limit = $ ______________
6. Henderson Family Winter Heating Target (4-Month Winter Season)
The Henderson family wants an average monthly winter heating bill of no more than $210.00 across Nov, Dec, Jan, and Feb. In Nov they spent $165.20, in Dec $235.80, and in Jan $258.40. What is their maximum budget for February?
1. Season Budget (Avg × 4)
Target = $ _____________
2. Known Sum (Nov+Dec+Jan)
Spent = $ ______________
3. Feb Limit (Subtract)
Limit = $ ______________
Part 4: Error Spotting (Common Pitfalls)
Scenario Analysis: A student was asked to find the 3rd quarter spending limit when the quarterly average target is $450. The student calculated: \( \$450 \times 2 = \$900 \), then subtracted the July and August expenses from $900.
What mistake did the student make?
How should the student fix this?
Unit 3: Budgeting & Expenses • Practice Worksheet Page 2 of 2
Topic 2: Career Budgets & Pitfalls Unit 3 Business Math
5. WE DO: Monthly Budget — University Professor
Slide 16
Annual Gross Salary: $54,750 / year. Standard Tax Deduction: 25%.
1. Gross Monthly Income
$54,750 ÷ 12 =
$ _________________
2. Tax Deductions (25%)
Gross × 0.25 =
$ _________________
3. Net Monthly Income
Gross − Deductions =
$ _________________
Essential Needs
• Rent (25%–28%): $ _________ – $ _________
• Utilities (7%–10%): $ _________ – $ _________
• Food (5%–9%): $ _________ – $ _________
Flexible & Personal
• Car Payment (10%–12%): $ _________ – $ _________
Never budget using Gross Salary! Always calculate using Net Monthly Income (after 25% tax).
2. Ignoring Flexible Expenses
Don't just plan rent/bills. Neglecting car, medical, and food leads to deficit cycles.
3. No Miscellaneous Fund
Always set aside 5% to 11% of net income for emergencies and unexpected costs.
Unit 3: Budgeting & Expenses • Packet 2 Page 2 of 2
Marcus has a Net Monthly Take-Home Income of $3,200. Using the unit's recommended budget ranges, calculate the exact minimum and maximum dollar amounts for each category.
Scenario: Elena earns a Gross Annual Salary of $56,400. Her total essential living expenses (housing, utilities, groceries, basic transit) average $1,850 per month.
1. Net Monthly Pay
Gross monthly minus 25% tax:
$ _________________
2. Leftover Surplus
Net Income − $1,850 Needs:
$ _________________
3. Emergency Savings (20%)
Leftover Surplus × 0.20:
$ _________________
Analysis Question: If Elena wants to allocate $300/month toward personal recreation and hobbies, can her leftover surplus comfortably cover it while still saving 20%? Explain.
Unit 3: Budgeting & Expenses • Practice Worksheet Page 2 of 2
Net Monthly Income: $ ________ − Total Expenditures: $ ________ = Remaining Surplus: $ ________ / mo
• Ensure Remaining Surplus is \(\ge \$0.00\). If negative, adjust flexible categories to eliminate deficit.
Unit 3: Personal Budgeting Project • Step-by-Step Guide Page 2 of 2
Utilities (7% – 10%)
Min: $4,125 × 0.07 = $ _________
Max: $4,125 × 0.10 = $ _________
Car Loan (10% – 12%)
Min: $4,125 × 0.10 = $ _________
Max: $4,125 × 0.12 = $ _________
Part 6: Cash Flow Surplus & Emergency Buffer
5. Jordan earns a Net Monthly Income of $3,500. His total essential expenditures (rent, utilities, groceries, transit) equal $2,100 each month.
A. Leftover Discretionary Surplus
Net Income − Essential Costs:
$ ____________________ / mo
B. Emergency Savings (20% of Surplus)
Surplus × 0.20:
$ ____________________ / mo
Jordan plans to spend $400 on dining out and entertainment. Will he still have enough left to fund his emergency savings goal? Explain.
Unit 3: Budgeting & Expenses • Comprehensive Review Page 2 of 2
Limit = $ ______________
Unit 3: Budgeting & Expenses • Summative Assessment Page 1 of 2
Unit 3 Test • Part 2: Income Deductions & Modeling Business Math Summative
Section 4: Gross to Net Salary Calculations
20 Points
Maya earns an Annual Gross Salary of $52,800. Complete the 3-step income deduction breakdown using the standard 25% tax rate.
9. Gross Monthly (\(\div 12\))
$52,800 ÷ 12 =
$ _________________
10. Tax Deductions (25%)
Gross Monthly × 0.25 =
$ _________________
11. Net Monthly Take-Home
Gross − Deductions =
$ _________________
Section 5: Target Budget Percentage Ranges
15 Points
Based on Maya’s Net Monthly Income of $3,300, calculate the recommended minimum and maximum monthly dollar limits for each category:
12. Housing (25% – 28%)
Min: $3,300 × 0.25 = $ ________
Max: $3,300 × 0.28 = $ ________
13. Utilities (7% – 10%)
Min: $3,300 × 0.07 = $ ________
Max: $3,300 × 0.10 = $ ________
14. Car Loan (10% – 12%)
Min: $3,300 × 0.10 = $ ________
Max: $3,300 × 0.12 = $ ________
Section 6: Applied Cash Flow & Pitfall Analysis
15 Points
15. Financial Scenario: David’s net monthly take-home income is $2,800. His total essential expenditures (rent, utilities, groceries, transportation) amount to $1,950 per month.
A. Calculate Discretionary Surplus
Net Income − Essential Needs:
$ ____________________ / mo
B. Emergency Savings (20% of Surplus)
Discretionary Surplus × 0.20:
$ ____________________ / mo
C. Conceptual Decision:
David wants to purchase a $450/month car and spend $250/month on recreation. Based on your calculations above, will his budget support both while maintaining his 20% emergency savings goal? Explain why or why not.
Unit 3: Budgeting & Expenses • Summative Assessment Page 2 of 2
