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Resources for undertaking an entrepreneurial project · Personal and project finance

Sources of finance and borrowing

A bicycle costs $\$240$. By saving $\$20$ a month, you can get it in a year at no extra cost. If the store finances it, you get it straight away, but at the price of an extra cost in the form of interest. Both options give you the same item; what sets them apart is the price of time. Understanding that price is the foundation of responsible finance.

Own funds and borrowed funds

Comparative diagram of own funds (savings and earnings, no obligation to repay) and borrowed money (loans, with an obligation to repay the principal plus interest). Ownsavings, earningsno repayment Borrowedloanrepayment + interest

What happens if you stop paying (default)? On a secured loan, the lender can repossess the car or start foreclosure on the house. On a credit card you face late fees, higher interest, calls from collectors and a lower credit score.

Young borrowers with no credit history are often asked for a cosigner: a person who promises to repay the loan if you don't. If you miss payments, the cosigner is legally responsible for the debt, and their credit score drops too. That is the risk a parent takes on when cosigning.

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You want a bicycle costing $\$240$. Explain the difference between paying for it with savings (you have been saving $\$20$ for months) and paying for it with an…

You want a bicycle costing $\$240$. Explain the difference between paying for it with savings (you have been saving $\$20$ for months) and paying for it with an "instant" loan offered by the store. What does each option gain and risk? In which scenarios would each option make sense?

Solve
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Explain the difference between own funding (savings, members' contributions) and external funding (loans, which must be repaid with interest). Classify: the $\$40…

Explain the difference between own funding (savings, members' contributions) and external funding (loans, which must be repaid with interest). Classify: the $\$40$ each member puts in, a loan from the PTA, last year's reinvested profits and a bank microloan.

Solve
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Name four sources of funding for the school project (the team's savings, a loan from the PTA, pre-selling vouchers, crowdfunding) and write one advantage and one…

Name four sources of funding for the school project (the team's savings, a loan from the PTA, pre-selling vouchers, crowdfunding) and write one advantage and one drawback of each in one sentence.

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Explain what a guarantor (cosigner) is and why banks ask for one from young people or those with no credit history. Take the case of your $19$-year-old cousin who…

Explain what a guarantor (cosigner) is and why banks ask for one from young people or those with no credit history. Take the case of your $19$-year-old cousin who applies for $\$3,000$ for a course and the bank requires her mother to act as cosigner: what risk does the mother take on?

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The school cooperative needs $\$300…

The school cooperative needs $\$300$ to start up the breakfast stall. Analyze four sources: the members' savings, a loan from the PTA (Parent-Teacher Association) to be repaid in $3$ months, an advance sale of breakfast vouchers to students, and reward-based crowdfunding. For each source, state: what it costs (money, commitment, work), what is risked, and what type of project it is best suited for.

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Simple interest

Graph showing how simple interest evolves over time, where the principal stays fixed and the same constant amount of interest is added in each period. Principal Pwhat you deposit × rinterest rate × ttime = Iinterest earned
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Interest is the cost of borrowing money. Calculate the simple interest on a deposit of $\$100$ at $5\ \%…

Interest is the cost of borrowing money. Calculate the simple interest on a deposit of $\$100$ at $5\ \%$ per year for one year: how many dollars does it generate and how much money do you end up with? What if you leave it for two years at simple interest?

Solve
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Calculate the simple interest of these loans with $I = C \times r \times t$: (a) $\$200$ at $5\ \%$ a year for $1$ year; (b) $\$200$ at $5\ \%$ a year for $3$ years; (c)…

Calculate the simple interest of these loans with $I = C \times r \times t$: (a) $\$200$ at $5\ \%$ a year for $1$ year; (b) $\$200$ at $5\ \%$ a year for $3$ years; (c) $\$500$ at $4\ \%$ a year for $2$ years. State in each case how much is repaid in total.

Solve
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Your grandmother lends you $\$500$ for your school project and (jokingly) charges you simple interest of $4\ \%…

Your grandmother lends you $\$500$ for your school project and (jokingly) charges you simple interest of $4\ \%$ per year. Calculate: (a) the interest for each year; (b) the amount you would repay her if you take $3$ years to pay her back; (c) the interest you would pay if you take only $6$ months. Remember that with simple interest, $I = C \times r \times t$.

Solve
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The co-op needs $\$400$ for a badge-making machine. The PTA lends it the money at $3\ \%$ simple annual interest, to be repaid in $8…

The co-op needs $\$400$ for a badge-making machine. The PTA lends it the money at $3\ \%$ simple annual interest, to be repaid in $8$ months.

  1. a) Calculate the total interest and what the co-op will repay (careful: $t$ in years, $8$ months is $8/12$ of a year).
  2. b) Compare with the option of waiting $8$ months, saving $\$50$ a month from the profits: what is gained and what is lost with each option if the big fair is in $3$ months' time.
Solve
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The school vegetable garden team wants $\$250$ for tools and is considering a pre-sale: selling $50$ basket vouchers of $\$5$ each, redeemable in June for a basket of…

The school vegetable garden team wants $\$250$ for tools and is considering a pre-sale: selling $50$ basket vouchers of $\$5$ each, redeemable in June for a basket of vegetables.

  1. a) Calculate how much they raise if they sell all the vouchers and explain how this funding differs from a loan (what they give back and when).
  2. b) Analyze the two main risks of the pre-sale (a bad harvest, more vouchers than baskets) and one measure for each.
Solve

Compound interest and the APR

Credit cards add two details. If you pay the full balance by the due date, the grace period means no interest on new purchases. Otherwise, interest is charged on your average daily balance: the average of what you owed on each day of the billing cycle.

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Define what the APR (annual percentage rate) is in your own words: what it tells you about a loan and why it is better than looking only at the monthly payment. An ad…

Define what the APR (annual percentage rate) is in your own words: what it tells you about a loan and why it is better than looking only at the monthly payment. An ad says "only $\$25$ a month": explain which two pieces of information you are missing to know how much you will pay in total.

Solve
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The figure compares two ways to grow $\$1,000$ at $10\ \%$ per year over $3…

The figure compares two ways to grow $\$1,000$ at $10\ \%$ per year over $3$ years: with simple interest (blue line, the same amount is added each time) and with compound interest (green curve, interest also earns interest).

years dollars 1000 1100 1200 1300 simple compound 1100 1210 1331 1300 1 2 3
  1. a) Read from the graph how much money there is after $3$ years with each method and calculate the difference.
  2. b) Explain in your own words why the green curve pulls further and further away from the blue line.
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An online store offers to finance a pair of $\$120$ sneakers in '$3$ interest-free installments of $\$40$', but charges $\$9…

An online store offers to finance a pair of $\$120$ sneakers in '$3$ interest-free installments of $\$40$', but charges $\$9$ of 'handling fees' at the start.

  1. a) Calculate how much you pay in total and what extra percentage that represents over the price.
  2. b) Explain why 'interest-free' does not mean 'free' and which two checks you would make before accepting any financing on an online purchase.
Solve
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You deposit $\$1,000$ at $5\ \%…

You deposit $\$1,000$ at $5\ \%$ per year with compound interest. Calculate the principal at the end of the first year and, using that result, the principal at the end of the second year (round to the nearest cent). Compare this with simple interest over two years and explain where the difference comes from.

Solve
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You deposit $\$800$ in an account at $3\ \%$ a year with compound interest. a) Calculate the balance after $1$ year and, from that result, after $2…

You deposit $\$800$ in an account at $3\ \%$ a year with compound interest.

  1. a) Calculate the balance after $1$ year and, from that result, after $2$ years (round to the nearest cent).
  2. b) Calculate the same with simple interest and explain where the difference comes from and why it would grow over the years.
Solve

The prudent limit of borrowing

Graph illustrating the responsible borrowing rule, limiting monthly debt payments to about 30% of income and keeping 70% for other expenses. 30% rule of thumb payments rest of income 0% 30% 100%
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Two loan ads for a $\$900$ computer: store A, $12$ installments of $\$82$; store B, $18$ installments of $\$56…

Two loan ads for a $\$900$ computer: store A, $12$ installments of $\$82$; store B, $18$ installments of $\$56$.

  1. a) Calculate the total paid and the cost of the financing at each store.
  2. b) Explain why the lowest installment (store B) works out more expensive in total and what practical rule follows about the length of consumer loans.
Solve
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You need a laptop costing $\$600$ for high school. Option A: save $\$60$ per month for $10$ months and buy it afterwards. Option B: store loan: you take it home today…

You need a laptop costing $\$600$ for high school. Option A: save $\$60$ per month for $10$ months and buy it afterwards. Option B: store loan: you take it home today and pay $12$ monthly installments of $\$54$.

  1. a) Calculate how much you pay in total with each option and how much "getting it early" in Option B costs in dollars and as a percentage of the price.
  2. b) Reason in which situations paying this extra cost could be justified and what questions you should ask yourself before signing.
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Lucas, aged $19$, earns a net salary of $\$950$ per month on a temporary contract. He lives with his family and contributes $\$200$ towards household expenses; in…

Lucas, aged $19$, earns a net salary of $\$950$ per month on a temporary contract. He lives with his family and contributes $\$200$ towards household expenses; in addition, he pays $\$45$ per month to finance his computer. He wants to buy a used motorcycle, and the dealership offers him two options:

  • Option A: An installment of $\$190$/month for $24$ months. The sales representative reassures him: "Your total debt will be $\$235$ per month, which is $24.7\ \%$ of your salary. The golden rule says that as long as you do not exceed $30\ \%$, you are in a completely safe zone."

  • Option B: A reduced installment of $\$120$/month for $48$ months with a final payment of $\$800$.

Insurance, gas, and maintenance for the motorcycle will entail an additional fixed cost of $\$110$ per month.

  1. a) Refute the sales representative's argument regarding Option A: calculate the real financial burden (total installments plus expenses associated with the vehicle) relative to his disposable income after contributing at home, and predict what would happen to his solvency if his working hours were reduced by $20\ \%$.
  2. b) Evaluate Option B: calculate the total cost of both options and justify which alternative Lucas should adopt to avoid over-indebtedness, taking into account the duration of his contract and his prior savings options.
Solve
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Financial well-being starts with having an emergency fund for unexpected events (repairs, medical costs, loss of income), usually worth $3$ to $6$ months of expenses.…

Financial well-being starts with having an emergency fund for unexpected events (repairs, medical costs, loss of income), usually worth $3$ to $6$ months of expenses. Design an emergency fund plan for Alex, who earns $\$20$ per week: estimate his essential weekly expenses, set how much he puts aside each week, and calculate how many weeks it will take to build an emergency fund worth two "months" of expenses. Explain what needs to happen for the plan to survive an expensive birthday or seasonal sales.

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Your $18$-year-old brother wants a $\$2,400$ motorcycle. He works weekends and earns $\$260$ a month. The shop offers to finance it over $24$ months with installments of…

Your $18$-year-old brother wants a $\$2,400$ motorcycle. He works weekends and earns $\$260$ a month. The shop offers to finance it over $24$ months with installments of $\$115$.

  1. a) Calculate the total cost of the financing and what percentage of his monthly income the installment represents (remember the $30\ \%$ benchmark as a prudent limit).
  2. b) Design an alternative mixed plan (saving for $6$ months first and then financing only the rest over $12$ months), calculate how much he saves in interest with your own reasonable assumptions and explain what else improves besides the money.
Solve
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The school cooperative has grown and needs $\$1,000$ for an oven. Three options: a loan from the PTA at $4\ \%$ a year for $1…

The school cooperative has grown and needs $\$1,000$ for an oven. Three options: a loan from the PTA at $4\ \%$ a year for $1$ year; a crowdfunding campaign with rewards (estimated cost of the rewards, $\$150$); selling $200$ stakes of $\$5$ entitling the holder to a free breakfast a month for the school year (estimated cost, $\$300$ in breakfasts).

  1. a) Calculate the cost of each option and order them from cheapest to most expensive.
  2. b) Explain what each option offers beyond the money (community commitment, publicity, the obligation to repay) and choose one, defending it in front of the members.
Solve
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Design your school cooperative's "funding policy" for the next $3$ years: what percentage of each project is funded with accumulated profits, when taking out a microloan…

Design your school cooperative's "funding policy" for the next $3$ years: what percentage of each project is funded with accumulated profits, when taking out a microloan is allowed (maximum amount, maximum term, who approves it) and which sources are banned and why (payday loans, undocumented debts between members). Defend the two rules that would generate the most debate.

Solve

Back to the start: If the store finances the $\$240$ bicycle for you in 12 monthly payments of $\$22$, you will pay $\$264$ in total: the $\$24$ difference is the interest, the price of enjoying the bicycle a year earlier.

Summary

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