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FEED • Stack 8KEY
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Answer Key
Stack 8
Check your answers for all five Vaults!
Vault 1
Money & Smart Spending
💼
Vault 2
Earning, Saving & Goals
📋
Vault 3
Budgeting & Money Management
🏛️
Vault 4
Banking & Digital Payments
📈
Vault 5
Growing Money & Tax
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Published by INFINTRIX | Edition 1 | 2026
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FEED • Stack 8KEY
Vault 1:
Money & Smart Spending
Activity A: Trade Flow Diagram
1. USA — Exports: IT services, gems; Imports: electronics
2. Saudi Arabia — Exports: rice, textiles; Imports: crude oil
3. China — Exports: iron ore; Imports: electronics, toys
4. Germany — Exports: spices, textiles; Imports: cars, machinery
5. UAE — Exports: jewellery, spices; Imports: oil, gold
Activity B: Exchange Rate Impact
1. Old ₹40,000 | New ₹44,000 | Extra ₹4,000
2. Old ₹1,600 | New ₹1,760 | Extra ₹160
3. Old ₹1,60,000 | New ₹1,76,000 | Extra earned ₹16,000
Activity C: Personal Values Rank
Open — evaluate student’s reasoning and whether their spending aligns with their stated values.
Activity D: Import Price Calculator
Base: $150 × 93 = ₹13,950
Duty (18%): ₹13,950 × 0.18 = ₹2,511
Shipping: ₹500
Total: ₹16,961
Savings vs Indian: ₹16,961 − ₹8,000 = ₹8,961
Activity E: Quick Quiz
Q1: b) Protect local manufacturers   Q2: b) Earn more in rupees   Q3: b) Crude oil   Q4: b) Live simply, use what you need   Q5: b) Thinking before spending
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Published by INFINTRIX | Edition 1 | 2026
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Vault 2:
Earning, Saving & Goals
Activity A: Classify the Income
1. Active   2. Passive   3. Passive   4. Active
5. Passive   6. Active   7. Passive   8. Active
Activity B: Break-Even Point
Break-even = 8,800 ÷ (400 − 180) = 8,800 ÷ 220 = 40 boxes.
If 60 boxes sold: Profit = (60 − 40) × 220 = ₹4,400.
Activity C: Mini P&L Statement
Revenue: 150 × ₹120 = ₹18,000
Total Expenses: 4,500 + 3,000 + 2,000 + 1,200 = ₹10,700
Net Profit = ₹18,000 − ₹10,700 = ₹7,300 (Profit)
Activity D: Contribution Margin or MoS?
1 = A (Contribution Margin)
2 = A (Contribution Margin — SP − VC)
3 = B (Margin of Safety)
4 = A (Contribution Margin)
5 = B (Margin of Safety)
Activity E: Quick Quiz
Q1: b) Rent from a flat you own   Q2: b) 50 units (15,000 ÷ 300 = 50)   Q3: b) Loss of ₹15,000   Q4: b) Selling Price − Variable Cost per unit   Q5: b) Barely above break-even
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Published by INFINTRIX | Edition 1 | 2026
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Vault 3:
Budgeting & Money Management
Activity A: 50-30-20 Rule
1. Needs (50%): ₹15,000 — rent, groceries, school fees
2. Wants (30%): ₹9,000 — eating out, movies, clothes
3. Savings (20%): ₹6,000 — RD, emergency fund
4. Total: ₹30,000
5. Rent ₹10,000 leaves only ₹5,000 for other needs — cut wants or find cheaper housing.
Activity B: Emergency Fund
1. Sharma: 3-mo ₹60,000 | 6-mo ₹1,20,000
2. Gupta: 3-mo ₹1,05,000 | 6-mo ₹2,10,000
3. Joshi: 3-mo ₹54,000 | 6-mo ₹1,08,000
4. Gupta 6-mo fund ÷ ₹5,000/mo = 42 months
Activity C: Match Money Habits
1 = B (Tutoring for pocket money)
2 = A (₹2,000/mo in RD)
3 = D (₹500 mutual fund SIP)
4 = E (Comparing prices before buying)
5 = C (Donating old clothes)
Activity D: Fix the Broken Budget
Budget 1: Wants 44% (should be 30%). Cut ₹3,500, add to savings.
Budget 2: Needs 70% (should be 50%). Review wants disguised as needs.
Budget 3: 0% savings! Reduce wants 50%→30%, save ₹4,000.
Activity E: Quick Quiz
Q1: c) 20%   Q2: c) ₹12,000 (30% of 40,000)   Q3: c) Monthly grocery shopping   Q4: b) 3 to 6 months   Q5: b) Borrow (5 habits: Earn, Save, Invest, Spend Wisely, Give)
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Published by INFINTRIX | Edition 1 | 2026
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Vault 4:
Banking & Digital Payments
Activity A: Spot the Phishing
1. PHISHING — personal number, no short code, urgency
2. GENUINE — official domain, no urgency
3. PHISHING — Yahoo email, http link, fake refund
4. GENUINE — bank short code, standard alert, helpline
Activity B: Password Strength
1. Weak — all numbers, 6 chars, common password
2. Medium — name-based, guessable
3. Strong — 14 chars with mix of upper/lower, numbers, symbols
Activity C: Real or Fake Website?
1. REAL — https, official .co.in domain
2. FAKE — http (no padlock), fake domain
3. REAL — https, official domain
4. FAKE — http, fake domain, suspicious URL
Activity D: 2FA Flow Order
Correct order: 4, 2, 5, 1, 3
Step 1: Enter username & password
Step 2: Server checks password, sends OTP
Step 3: Receive OTP on phone
Step 4: Enter OTP in verification field
Step 5: Both verified — access granted
Activity E: Quick Quiz
Q1: b) Two-Factor Authentication   Q2: b) Sender uses a Gmail address   Q3: c) URL has https:// and padlock   Q4: c) Your OTP, PIN, or CVV on call   Q5: c) Transferring money via NEFT/IMPS
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Published by INFINTRIX | Edition 1 | 2026
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Vault 5:
Growing Money & Tax
Activity A: SIP Growth Calculator
₹500/mo: 5yr ~₹41,000 | 10yr ~₹1,16,000 | 20yr ~₹5,00,000
₹1,000/mo: 5yr ~₹82,000 | 10yr ~₹2,32,000 | 20yr ~₹10,00,000
₹2,000/mo: 5yr ~₹1,64,000 | 10yr ~₹4,64,000 | 20yr ~₹20,00,000
Open-ended reasoning about compounding & time.
Activity B: GST Calculator
Milk: GST ₹0, Total ₹100
Sugar: GST ₹2.50, Total ₹52.50
Butter: GST ₹30, Total ₹280
Soap: GST ₹36, Total ₹236
Perfume: GST ₹280, Total ₹1,280
Grand Total: GST ₹348.50, Total ₹1,948.50
Activity C: Calculate Income Tax
Person 1 (₹10L): Nil + ₹20,000 + ₹20,000 = ₹40,000 slab tax. Income ≤ ₹12L → 87A rebate → Effective tax = ₹0.
Person 2 (₹14L): Nil + ₹20,000 + ₹40,000 + ₹30,000 = ₹90,000.
Activity D: Stock or Mutual Fund?
Priya: Mutual Fund (SIP) — long-term, hands-off
Amit: Stocks — has knowledge, researches
Grandma: Mutual Fund — safe, managed by experts
Rohan: Stocks — high risk/high return, accepts losses
Activity E: Quick Quiz
Q1: b) Systematic Investment Plan   Q2: c) Part-owner   Q3: c) 0% (No tax)   Q4: d) 0%   Q5: b) Mutual fund
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Published by INFINTRIX | Edition 1 | 2026