Worked examples
Real scenarios with real numbers, calculated deterministically — see the maths before you trust it.
The full anatomy of a typical mortgage: monthly repayment, total interest, and how the balance falls year by year.
Example Starting at 25 vs starting at 35Ten years’ head start, same monthly saving: the gap at retirement is bigger than most people guess.
Example The best ways to spend leave days in Argentina in 2026Where Argentina's 2026 public holidays already lean your way: the year's best bridges and blocks, computed from the calendar.
Example The best ways to spend leave days in Australia in 2026Where Australia's 2026 public holidays already lean your way: the year's best bridges and blocks, computed from the calendar.
Example The best ways to spend leave days in Brazil in 2026Where Brazil's 2026 public holidays already lean your way: the year's best bridges and blocks, computed from the calendar.
Example The best ways to spend leave days in Canada in 2026Where Canada's 2026 public holidays already lean your way: the year's best bridges and blocks, computed from the calendar.
Example The best ways to spend leave days in France in 2026Where France's 2026 public holidays already lean your way: the year's best bridges and blocks, computed from the calendar.
Example The best ways to spend leave days in Germany in 2026Where Germany's 2026 public holidays already lean your way: the year's best bridges and blocks, computed from the calendar.
Example The best ways to spend leave days in Ireland in 2026Where Ireland's 2026 public holidays already lean your way: the year's best bridges and blocks, computed from the calendar.
Example The best ways to spend leave days in Italy in 2026Where Italy's 2026 public holidays already lean your way: the year's best bridges and blocks, computed from the calendar.
Example The best ways to spend leave days in Mexico in 2026Where Mexico's 2026 public holidays already lean your way: the year's best bridges and blocks, computed from the calendar.
Example The best ways to spend leave days in Netherlands in 2026Where Netherlands's 2026 public holidays already lean your way: the year's best bridges and blocks, computed from the calendar.
Example The best ways to spend leave days in New Zealand in 2026Where New Zealand's 2026 public holidays already lean your way: the year's best bridges and blocks, computed from the calendar.
Example The best ways to spend leave days in Poland in 2026Where Poland's 2026 public holidays already lean your way: the year's best bridges and blocks, computed from the calendar.
Example The best ways to spend leave days in Portugal in 2026Where Portugal's 2026 public holidays already lean your way: the year's best bridges and blocks, computed from the calendar.
Example The best ways to spend leave days in Spain in 2026Where Spain's 2026 public holidays already lean your way: the year's best bridges and blocks, computed from the calendar.
Example The best ways to spend leave days in United Kingdom in 2026Where United Kingdom's 2026 public holidays already lean your way: the year's best bridges and blocks, computed from the calendar.
Example The best ways to spend leave days in United States in 2026Where United States's 2026 public holidays already lean your way: the year's best bridges and blocks, computed from the calendar.
Example Overpaying a mortgage by €100 a monthWhat a steady €100 overpayment does to a €300,000 mortgage: the years removed and the interest saved.
Example How many working days are in 2026?The weekday arithmetic of one year, worked through: total days, weekends, and Monday-to-Friday working days.
Example Down 20%, up 25%: why falls need bigger risesA worked example of percentage asymmetry: what falls by 20% must rise by 25% just to get back where it started.
Example What €100 buys after 20 years of inflationThe quiet arithmetic of 2% a year: what today’s €100 of shopping costs in 10, 20 and 35 years.
Example €100 a month for 30 yearsA worked example of steady small saving: what €100 a month becomes over 30 years at different rates.
Example When savings lose money while growingA worked example of negative real returns: 2% interest under 5% inflation is a loss wearing a plus sign.
Example The same mortgage over 25, 30 and 35 yearsOne loan, three terms: how the monthly payment and the lifetime interest trade against each other.
Example Why 20% off then 10% off isn’t 30% offA worked example of stacked percentages: successive discounts multiply rather than add, and the gap is real money.
Example Born on 29 February: how leap-day birthdays workA 29 February birthday arrives every four years — how the maths of leap-day ages actually works out.
Example VAT on €100, worked throughWhat the standard and reduced Irish rates each do to a €100 net price — and how to read the gross that results.
Example A €10,000 lump sum left for 20 yearsWhat happens when you invest once and leave it alone — €10,000 over 20 years at different rates.
Example Removing VAT from a priceGetting the net out of a VAT-inclusive price: divide, never subtract — worked with real numbers.
Example How fast money doubles at different ratesExact doubling times from 1% to 12%, side by side with the Rule of 72 estimate.
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