MAT8 Q2W8D2: Identifying Financial Problems in Real-Life Situations

🎯 Learning Goals

By the end of the lesson, you will be able to:

1. Describe at least four common financial problems faced by learners and families (for example income-expense mismatch, debt, unexpected expenses, lack of budgeting) and explain their causes and effects.
2. Classify real-life scenarios as earning money, profit and loss, best buys (cost per unit), or buying on terms (installment) using clear criteria.
3. Analyze a given scenario and compute simple quantities (for example deficit or surplus, cost per unit) using correct MathML to support your explanation.

🧩 Key Ideas & Terms

• Income - money received such as allowance, salary, or sales. $I$
• Expense - money paid out such as food, transport, or bills. $E$
• Surplus - amount left when income exceeds expenses. $\mathrm{Surplus}=I-E,I>E$
• Deficit - shortage when expenses exceed income. $\mathrm{Deficit}=E-I,E>I$
• Debt - money owed to a person or institution that can grow with interest.
• Interest - cost of borrowing or reward for saving. Simple interest: $I=P\times r\times t$ where $P$ is principal, $r$ is rate per year, and $t$ is time in years.
• Emergency fund - savings reserved for unexpected needs such as medical or repairs, typically equal to several months of expenses.
• Best buy (cost per unit) - compares value by price per unit. $\text{Cost per unit}=\frac{\mathrm{Price}}{\mathrm{Quantity}}$
• Installment - paying for an item over time in fixed parts. Basic payment without added charges: $\text{Payment per period}=\frac{\text{Total price}}{\text{Number of periods}}$. If interest or fees apply then the total price increases.
• Budget - plan that allocates income to expenses, savings, and goals so that $I=E+\text{Savings}$.

🔄 Quick Recall / Prior Knowledge

Activity A: Sort It Fast (Income vs Expense)

List each item as Income or Expense: 1) Weekend tutoring pay 2) Phone load 3) Allowance 4) Notebook purchase 5) Selling pre-loved items.

Show Answer

Income: 1, 3, 5. Expense: 2, 4.

Activity B: Surplus or Deficit

A learner’s monthly income is ₱3,200 and expenses total ₱3,450. State whether this is a surplus or deficit and compute the amount.

Show Answer

It is a deficit.

$\mathrm{Deficit}=E-I=3450-3200=250$

Activity C: Classify the Situation

Label each as earning money, profit and loss, best buy (cost per unit), or installment. 1) Compare 1.5 L at ₱72 vs 2 L at ₱95. 2) Paid weekend pet-sitting. 3) Selling stickers after spending ₱500 on materials. 4) Phone on a 12-month pay plan.

Show Answer

1) Best buy 2) Earning money 3) Profit and loss 4) Installment.

Activity D: Quick Cost-per-Unit

Which is cheaper per liter: 1.5 L juice at ₱72 or 2 L juice at ₱95? Show the computation.

Show Answer

1.5 L:

$\text{₱/L}=\frac{72}{1.5}=48$

2 L:

$\text{₱/L}=\frac{95}{2}=47.5$

Cheaper: 2 L at ₱47.50 per liter.

Activity E: Simple Interest Recall

Write the simple interest formula and identify each symbol. Then compute the interest on ₱4,000 at 5 percent per year for 2 years.

Show Answer

Formula:

$I=P\times r\times t$

Computation:

$I=4000\times 0.05\times 2=400$

Activity F: Needs vs Wants

Mark Need or Want: data for school research, branded earbuds, school uniform replacement, ride-share to skip walking a short distance.

Show Answer

Need: data for school research, uniform replacement. Want: branded earbuds, optional ride-share for short distance.

📖 Explore the Lesson: Describe Situations Involving Financial Problems

Today you will describe and make sense of real-life financial problems that students and families commonly face. Use four lenses: earning money, profit and loss, best buys, and buying on terms. Read each situation, pull out who, what, numbers, and when, classify it, and support your description with a small computation using MathML.

1) Reading a Situation - a simple checklist

• Who is involved
• What decision or problem is happening
• Numbers you can compute with
• When it happens
• Which lens applies

Guiding question: Which words usually signal a best buy problem

Show Answer

Words like per unit, per kilogram, per liter, per piece, and questions such as “Which is cheaper per ...” signal a best buy situation.

Mini-Summary: A money story becomes clearer when you pull out who, what, numbers, when, and the lens that fits.

2) Individual-level problems

Situation A - Allowance stretch

Weekly allowance ₱600. Weekly plan: food ₱360, transport ₱180, savings ₱100.

Question A1. Surplus or deficit

Show Answer

Total planned:

$360+180+100=640$

Income is ₱600 so there is a deficit of

$640-600=40$ pesos.

Question A2. Which lens applies

Show Answer

This is a budget balance description that highlights surplus or deficit. It connects to problem identification and planning adjustments.

Mini-Summary: When expenses exceed income you are describing a deficit that needs action.

Situation B - Prepaid data vs Wi-Fi share

Option 1: 6 GB for ₱120. Option 2: contribute ₱300 per month for shared Wi-Fi and you use about 18 GB monthly.

Question B1. Compute cost per GB for each option

Show Answer

Option 1:

$\text{₱/GB}=\frac{120}{6}=20$

Option 2:

$\text{₱/GB}=\frac{300}{18}=16.67$

Question B2. Classify the situation and explain

Show Answer

This is a best buy situation because you compare unit costs. The shared Wi-Fi is cheaper per GB for the stated usage.

Mini-Summary: Best buy descriptions state the unit, compute cost per unit, and compare.

Situation C - Weekend skill gigs

Option A: tutoring ₱150 per hour, 3 hours every Saturday. Option B: baking and selling 24 cupcakes at ₱25 each; ingredients ₱280, boxes ₱60.

Question C1. Describe earnings in Option A

Show Answer

One weekend:

$150\times 3=450$

Four weekends:

$450\times 4=1800$

Question C2. For Option B compute revenue, cost, and profit

Show Answer

Revenue:

$24\times 25=600$

Cost:

$280+60=340$

Profit:

$600-340=260$

Question C3. Classify both options

Show Answer

Option A is earning money. Option B is profit and loss.

Mini-Summary: A clear description says whether money comes from hours worked or from selling goods.

3) Household-level problems

Situation D - Unexpected medicine expense

Planned grocery ₱2,500 and transport ₱600. An extra medicine purchase of ₱1,200 is needed. Available income is ₱3,200.

Question D1. Surplus or deficit and by how much

Show Answer

Planned grocery + transport:

$2500+600=3100$

With medicine:

$3100+1200=4300$

Income is ₱3,200 so deficit:

$4300-3200=1100$

Question D2. Name two lenses to respond to this deficit

Show Answer

Earning money to add income and best buy to reduce expenses by selecting lower unit cost alternatives.

Mini-Summary: Emergencies can create a deficit. Responses include earning more or spending less wisely.

Situation E - Rice purchase size

At a store: 5 kg rice at ₱260 and 10 kg rice at ₱500.

Question E1. Compute cost per kilogram and choose the best buy

Show Answer

5 kg pack:

$\text{₱/kg}=\frac{260}{5}=52$

10 kg pack:

$\text{₱/kg}=\frac{500}{10}=50$

Best buy: 10 kg at ₱50 per kg.

Question E2. When might 5 kg still be practical

Show Answer

When cash is limited today or storage space is small. Unit cost is higher but the smaller pack may be the only feasible choice.

Mini-Summary: Best buy is about value per unit but constraints like cash and storage also matter.

4) School and community situations

Situation F - Fund-raiser T-shirts

Printer plans: Plan 1 - ₱220 per shirt, minimum 20. Plan 2 - ₱180 per shirt, minimum 50, setup fee ₱800.

Question F1. With 20 shirts compute total cost for each plan and decide

Show Answer

Plan 1 (20 shirts):

$220\times 20=4400$

Plan 2 cannot be used at 20 due to minimum 50. Plan 1 is the only feasible option.

Question F2. With 50 shirts compute total cost for each plan and choose

Show Answer

Plan 1 (50 shirts):

$220\times 50=11000$

Plan 2 (50 shirts):

$180\times 50=9000$

Add setup fee:

$9000+800=9800$

Choose Plan 2 at ₱9,800.

Mini-Summary: When a deal has a setup fee compute total cost at the minimum and above it to see when it becomes better.

Situation G - Canteen snacks comparison

Item A: 150 g chips at ₱34. Item B: 250 g chips at ₱56.

Question G1. Compute cost per gram and choose the better buy

Show Answer

A:

$\text{₱/g}=\frac{34}{150}=0.2267$

B:

$\text{₱/g}=\frac{56}{250}=0.224$

Better buy: B (slightly lower cost per gram).

Mini-Summary: Best buy descriptions always state the unit and the computed unit cost.

5) Installment planning

Situation H - Calculator on terms

Cash price ₱1,800. Installment: 3 months at 0 percent interest, equal payments, service fee ₱60 per month.

Question H1. Monthly payment on installment and total versus cash

Show Answer

Base payment per month:

$\frac{1800}{3}=600$

Monthly outlay with fee:

$600+60=660$

Total on installment:

$660\times 3=1980$

Extra cost versus cash: ₱180.

Question H2. Classification

Show Answer

Buying on terms (installment). Even with 0 percent interest the fees increase total cost.

Mini-Summary: In installment descriptions include term length, fees, and total paid.

6) Profit and loss in a small venture

Situation I - Sticker micro-business

Price per set ₱35. Produce 40 sets. Costs: paper and ink ₱520, cutting mats ₱60, packaging ₱80.

Question I1. Weekly revenue and total cost

Show Answer

Revenue:

$40\times 35=1400$

Total cost:

$520+60+80=660$

Question I2. Profit

Show Answer

Profit:

$1400-660=740$

Mini-Summary: Profit or loss is revenue minus cost. Include one-time fees in cost.

7) Layered case studies

Case 1 - Commuter pass or per-ride

20 school days per month. Fare ₱16 per ride. Two rides per day. Pass ₱560 up to 50 rides.

Task 1. Per-month cost if paying per ride

Show Answer

Rides per month:

$20\times 2=40$

Cost:

$40\times 16=640$

Task 2. Compare with the pass and decide

Show Answer

Pass ₱560 vs ₱640 per-ride. Savings:

$640-560=80$

Pass is better.

Mini-Summary: Count rides then compare total cost with the pass.

Case 2 - Resell-and-ride

Buy 12 transit cards at ₱28 and resell at ₱35. Kiosk fee ₱60. Goal is to buy a helmet at ₱650 using profit plus ₱300 saved.

Task 1. Total cost, revenue, and profit

Show Answer

Total cost:

$12\times 28=336$

Add fee:

$336+60=396$

Revenue:

$12\times 35=420$

Profit:

$420-396=24$

Task 2. Amount still needed for the helmet

Show Answer

Profit plus savings:

$24+300=324$

Gap:

$650-324=326$

Mini-Summary: Include one-time fees in cost before computing profit.

Case 3 - Laptop on terms vs save-then-buy

Cash price ₱28,000. Plan A: 12 months equal shares plus a 2 percent monthly handling fee on remaining balance. Plan B: save ₱2,800 monthly for 10 months.

Task 1. Base payment and month-1 fee for Plan A

Show Answer

Base per month (no fees):

$\frac{28000}{12}=2333.33$

Month-1 fee:

$0.02\times 28000=560$

Task 2. Month-2 fee after one base payment

Show Answer

New balance:

$28000-2333.33=25666.67$

Fee month 2:

$0.02\times 25666.67=513.33$

Task 3. Key difference between plans

Show Answer

Plan A gives the laptop now but adds fees that raise total cost. Plan B delays the purchase but avoids extra fees by paying cash after saving.

Mini-Summary: Installments add fees over time while saving first lowers total cost if you can wait.

8) Common pitfalls and a template

• Always include service or handling fees in totals.
• Compare by unit cost for best buy problems.
• State whether values are per day, week, or month.
• Profit is revenue minus cost. Cash on hand can differ if items remain unsold.

Checkpoint: Which unit should be used for shampoo sachets 8 ml at some price vs 12 ml at some price

Show Answer

Milliliters. Compute cost per ml for each and compare.

Mini-Summary: Clear descriptions include all costs, unit choice, and time frame.

9) Practice-style scenario descriptions

Scenario 1 - Print credits bundle

Bundle A: 25 pages for ₱30. Bundle B: 50 pages for ₱56. Describe the best buy using cost per page.

Show Answer

A:

$\text{₱/page}=\frac{30}{25}=1.2$

B:

$\text{₱/page}=\frac{56}{50}=1.12$

Cheaper per page: Bundle B.

Scenario 2 - Part-time hours

Coach at ₱120 per hour for 2 hours on Friday and 3 hours on Saturday. Describe weekly earnings.

Show Answer

Total hours:

$2+3=5$

Earnings:

$120\times 5=600$

Scenario 3 - Bake sale pricing

Costs: flour ₱120, sugar ₱80, butter ₱180, eggs ₱70, gas ₱60. Make 30 brownies and sell at ₱18 each. Describe revenue and profit or loss.

Show Answer

Cost:

$120+80+180+70+60=510$

Revenue:

$30\times 18=540$

Profit:

$540-510=30$

Scenario 4 - Phone load packs

Pack X: 7 days, 3 GB for ₱90. Pack Y: 15 days, 6.5 GB for ₱170. Usage is 6 GB per two weeks. Describe the better fit and value.

Show Answer

X:

$\text{₱/GB}=\frac{90}{3}=30$

Y:

$\text{₱/GB}=\frac{170}{6.5}=26.15$

Pack Y is cheaper per GB and matches the two-week span.

Scenario 5 - Uniform on installments

Uniform set costs ₱1,200. Installment offer: 4 months equal base payment plus service fee ₱25 per month. Describe monthly outlay and total paid.

Show Answer

Base per month:

$\frac{1200}{4}=300$

Monthly outlay with fee:

$300+25=325$

Total paid:

$325\times 4=1300$

10) Describe with criteria - a quick template

Use a three-sentence template: type and context, key numbers with time unit, and the reasoned conclusion based on a computed value.

Checkpoint: Write your own three-sentence description for snack choice 45 g at ₱17 vs 65 g at ₱23.

Show Answer

Type: best buy. Key numbers: 45 g at ₱17 and 65 g at ₱23. Conclusion based on unit costs:

$\text{₱/g (45 g)}=\frac{17}{45}\approx 0.378,\text{₱/g (65 g)}=\frac{23}{65}\approx 0.354$

65 g is the better buy.

11) Mixed vignettes

Vignette 1 - Load share or personal promo

Need 10 GB in 10 days. Friend offers 5 GB for ₱120, up to 2 shares. Personal promo is 12 GB for ₱310.

Show Answer

Two shares: 10 GB for ₱240 which is ₱24 per GB. Personal promo is about ₱25.83 per GB. Both meet the need. Better value: load share.

Vignette 2 - Part-time weekend target

Target save ₱2,400 in 6 weeks. Rate ₱160 per hour, 2 hours per Saturday and Sunday.

Show Answer

Hours per week:

$2+2=4$

Weekly earnings:

$160\times 4=640$

Six weeks:

$640\times 6=3840$

Goal is reachable with a surplus of ₱1,440.

Vignette 3 - Club hoodies order

Supplier A: ₱750 each, minimum 12, free logo. Supplier B: ₱680 each, minimum 12, logo fee ₱600 per batch.

Show Answer

Total for 12 with A:

$750\times 12=9000$

Total for 12 with B:

$680\times 12=8160$

Add fee:

$8160+600=8760$

Cheaper: Supplier B.

Vignette 4 - Shoes on terms

Price ₱2,400. Three months equal base payment, admin fee ₱40 per month.

Show Answer

Base per month:

$\frac{2400}{3}=800$

Monthly outlay with fee:

$800+40=840$

Total:

$840\times 3=2520$

Vignette 5 - Photo-print micro-biz

Ink ₱200, paper ₱150 for 50 sheets, electricity ₱50. Sell 40 prints at ₱15.

Show Answer

Cost:

$200+150+50=400$

Revenue:

$40\times 15=600$

Profit:

$600-400=200$

12) Short numeric toolbox

• Surplus or deficit: $\mathrm{Surplus}=I-E,\mathrm{Deficit}=E-I$
• Profit or loss: $\mathrm{Profit}=\mathrm{Revenue}-\mathrm{Cost}$
• Cost per unit: $\text{Cost per unit}=\frac{\mathrm{Price}}{\mathrm{Quantity}}$
• Simple interest: $I=P\times r\times t$
• Equal installment without interest: $\text{Payment per period}=\frac{\text{Total price}}{\text{Number of periods}}$

13) Reflection prompts

• What signals tell you a problem is best buy and not profit
• When would you choose installment even if it costs more overall
• Which earner type suits your schedule and skills - hourly work or selling goods

References

• Investopedia. Financial planning.
• Organisation for Economic Co-operation and Development. Financial Literacy Questionnaire for PISA 2022.
• VISA. Practical Money Skills Workbook.
• The Skills That Matter in Adult Education. Money Management Lesson Plan.
• Wealthy Woman Finance. Financial Literacy Month ideas.

💡 Example in Action

Worked Example 1 - Grocery best buy (rice)

5 kg at ₱260 vs 10 kg at ₱500. Describe which is better using cost per kilogram and classify.

Show Answer

Best buy classification.

5 kg:

$\text{₱/kg}=\frac{260}{5}=52$

10 kg:

$\text{₱/kg}=\frac{500}{10}=50$

Better buy is 10 kg at ₱50 per kg.

Worked Example 2 - Small venture (profit and loss)

30 brownies, costs ₱120 + ₱80 + ₱180 + ₱70 + ₱60, price ₱18 each.

Show Answer

Revenue:

$30\times 18=540$

Cost:

$120+80+180+70+60=510$

Profit:

$540-510=30$

Worked Example 3 - Part-time work (earning money)

Rate ₱150 per hour for 2 hours on Friday and 3 hours on Saturday.

Show Answer

Total hours:

$2+3=5$

Weekly earnings:

$150\times 5=750$

Worked Example 4 - School calculator on terms (installment)

Cash price ₱1,800. Installment: 3 months, equal base, service fee ₱60 per month.

Show Answer

Base per month:

$\frac{1800}{3}=600$

Monthly outlay:

$600+60=660$

Total paid:

$660\times 3=1980$

Worked Example 5 - Mobile data choice (best buy with usage)

Pack X: 7 days, 3 GB for ₱90. Pack Y: 15 days, 6.5 GB for ₱170. Use about 6 GB per two weeks.

Show Answer

X:

$\text{₱/GB}=\frac{90}{3}=30$

Y:

$\text{₱/GB}=\frac{170}{6.5}=26.15$

Pack Y is cheaper per GB and matches the timing.

Now You Try

Task 1 - Detergent sachets (best buy): 28 g for ₱10 vs 45 g for ₱16.

Show Answer

A:

$\text{₱/g}=\frac{10}{28}\approx 0.357$

B:

$\text{₱/g}=\frac{16}{45}\approx 0.356$

Cheaper per gram: B.

Task 2 - Weekend job goal (earning money): Need ₱2,400 in 6 weeks. Rate ₱160 per hour, 2 hours Sat and 2 hours Sun.

Show Answer

Weekly earnings:

$160\times 4=640$

Six weeks total:

$640\times 6=3840$

Goal is reachable with surplus ₱1,440.

Task 3 - Bookmark sales (profit and loss): Materials ₱180; 24 bookmarks at ₱15.

Show Answer

Revenue:

$24\times 15=360$

Profit:

$360-180=180$

Task 4 - Uniform set on installments (installment): Price ₱1,200, 4 months, fee ₱25 per month.

Show Answer

Base per month:

$\frac{1200}{4}=300$

Monthly outlay with fee:

$300+25=325$

Total paid:

$325\times 4=1300$

Task 5 - Commuter pass vs paying per ride (best buy): Fare ₱16 per ride, 2 rides per day, 20 school days, pass ₱560.

Show Answer

Rides needed:

$20\times 2=40$

Pay per ride:

$40\times 16=640$

Pass is cheaper by

$640-560=80$

📝 Try It Out

Describe, classify, and support with MathML computations.

1) Weekly budget balance: Allowance ₱3,600. Expenses: food ₱1,600, transport ₱800, school ₱900, others ₱400. Surplus or deficit and by how much

Show Answer

Total expenses:

$1600+800+900+400=3700$

Deficit:

$\mathrm{Deficit}=3700-3600=100$

2) Milk value check: 1.5 L ₱78 vs 2.0 L ₱95. Which is cheaper per liter

Show Answer

1.5 L:

$\text{₱/L}=\frac{78}{1.5}=52$

2.0 L:

$\text{₱/L}=\frac{95}{2}=47.5$

Cheaper per liter: 2.0 L.

3) Weekend coaching pay: ₱180 per hour, hours 2 + 1 + 2 in a week. Earnings

Show Answer

Total hours:

$2+1+2=5$

Earnings:

$180\times 5=900$

4) Keychain micro-business: Sell 35 at ₱25. Materials ₱550, stall ₱100. Revenue, cost, profit

Show Answer

Revenue:

$35\times 25=875$

Cost:

$550+100=650$

Profit:

$875-650=225$

5) Phone on terms: Cash ₱9,600. Six months with fee ₱75 per month. Base, monthly outlay, total, extra vs cash

Show Answer

Base per month:

$\frac{9600}{6}=1600$

Monthly outlay:

$1600+75=1675$

Total:

$1675\times 6=10050$

Extra vs cash:

$10050-9600=450$

6) Data plan comparison: Plan A 10 GB ₱270. Plan B 7 GB ₱196. Lower ₱ per GB and fit for 14 days at 8 GB

Show Answer

A:

$\text{₱/GB}=\frac{270}{10}=27$

B:

$\text{₱/GB}=\frac{196}{7}=28$

Cheaper per GB: Plan A. It covers 8 GB over two weeks.

7) Commuter pass decision: Fare ₱17 per ride, 22 days, 2 rides per day, pass ₱700 up to 50 rides

Show Answer

Rides needed:

$22\times 2=44$

Pay per ride cost:

$44\times 17=748$

Pass is cheaper by:

$748-700=48$

8) Sugar bundle: 1 kg ₱68 vs 2 kg ₱130. Which is cheaper per kg

Show Answer

1 kg:

$\text{₱/kg}=\frac{68}{1}=68$

2 kg:

$\text{₱/kg}=\frac{130}{2}=65$

Cheaper per kg: 2 kg pack.

9) Unexpected expense shock: Planned ₱3,000. Medicine ₱1,400. Income ₱3,100. Surplus or deficit

Show Answer

Total needs:

$3000+1400=4400$

Deficit:

$\mathrm{Deficit}=4400-3100=1300$

10) Notebook sales with setup cost: 60 notebooks at ₱18. Costs: paper and ink ₱620, binding ₱180, stall fee ₱150.

Show Answer

Revenue:

$60\times 18=1080$

Total cost:

$620+180+150=950$

Profit:

$1080-950=130$

✅ Check Yourself

Answer each item then open the hidden answer to check.

1) Lens ID: Compute ₱ per kilogram to compare two rice sacks. What lens is this

Show Answer

Best buy (cost per unit).

2) Milk comparison: 1.5 L ₱84 vs 2.0 L ₱108. Which is cheaper per liter

Show Answer

1.5 L:

$\text{₱/L}=\frac{84}{1.5}=56$

2.0 L:

$\text{₱/L}=\frac{108}{2}=54$

Cheaper per liter: 2.0 L. Lens: best buy.

3) Allowance check: Income ₱3,200; expenses ₱2,950. Surplus or deficit and amount

Show Answer

Surplus:

$\mathrm{Surplus}=3200-2950=250$

4) Keychain sales: Sell 18 at ₱40. Materials ₱380, transport ₱120. Revenue, cost, profit

Show Answer

Revenue:

$18\times 40=720$

Cost:

$380+120=500$

Profit:

$720-500=220$

5) Phone on terms: Cash ₱3,600. Three months, fee ₱45 per month. Base, monthly outlay, total, extra vs cash

Show Answer

Base:

$\frac{3600}{3}=1200$

Monthly outlay:

$1200+45=1245$

Total paid:

$1245\times 3=3735$

Extra vs cash:

$3735-3600=135$

6) Commuter pass: Fare ₱15, 20 days, 2 rides per day. Pass ₱560. Which is cheaper

Show Answer

Rides:

$20\times 2=40$

Pay per ride cost:

$40\times 15=600$

Pass at ₱560 is cheaper by ₱40.

7) Two-week goal via hours: Rate ₱140 per hour; 12 hours per week for 2 weeks. Goal ₱1,500. Reachable

Show Answer

Two weeks earnings:

$140\times 12\times 2=3360$

Goal is reachable.

8) Cereal packs: 750 g ₱120 vs 1 kg ₱155. Which is cheaper per kg

Show Answer

0.75 kg pack:

$\text{₱/kg}=\frac{120}{0.75}=160$

1 kg pack:

$\text{₱/kg}=\frac{155}{1}=155$

Cheaper per kg: 1 kg pack.

9) Cupcake stall: Sell 25 at ₱30. Ingredients ₱300, packaging ₱50, stall fee ₱100.

Show Answer

Revenue:

$25\times 30=750$

Cost:

$300+50+100=450$

Profit:

$750-450=300$

10) Expense shock: Planned ₱2,800, medicine ₱900, income ₱3,400. Surplus or deficit

Show Answer

Total needs:

$2800+900=3700$

Deficit:

$\mathrm{Deficit}=3700-3400=300$

🚀 Go Further

1) Pantry refill plan under a cash limit

Cash limit ₱1,000. Choose rice and cooking oil options and compare unit values.

Show Answer

Rice 10 kg at ₱500 is ₱50 per kg and oil 1.8 L at ₱250 is about ₱138.89 per liter. Total is ₱750 and fits the limit with better unit values than smaller packs.

2) Break-even analysis for a pop-up stall

Price ₱35, variable cost ₱22, fixed fee ₱390.

Show Answer

Margin per unit is ₱13. Break-even quantity is

$\frac{390}{13}=30$

sandwiches.

3) Threshold rides for a commuter pass

Jeepney fare ₱17 per ride. Pass ₱720 up to 60 rides. Find the ride threshold and check for 22 school days at 2 rides per day.

Show Answer

Threshold when pass is cheaper:

$R\ge \frac{720}{17}\approx 42.35$

So 43 rides or more. For 22 days at 2 per day equals 44 rides so pass is cheaper.

4) Installment vs save-then-buy with savings interest

Tablet cash ₱12,000. Installment fee ₱60 per month for 6 months. Save ₱2,000 monthly at 2 percent simple interest per year.

Show Answer

Installment monthly outlay ₱2,060 and total ₱12,360. Save-then-buy principal ₱12,000 and about ₱60 interest over 6 months based on average balance. Lower total cost is save-then-buy if you can wait.

5) Build a best-buy mini price board

Collect two sizes and prices for shampoo and detergent then compute unit costs and choose the best buy with one-sentence descriptions.

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Compute ₱ per ml for shampoo and ₱ per g for detergent. Choose the lower unit price for each product and explain the choice in one sentence.

🔗 My Reflection

Answer in your notebook.

1. Describe one real financial situation you observed at home, in school, or in your community this month.
2. Identify the lens that best fits it and explain why.
3. Write one short computation that supports your description using MathML.
4. State one action you would recommend to improve the situation and justify it.
5. Reflect on what you learned about making choices with limited money.