Blog
Notes behind the numbers
Short, worked explanations of the arithmetic the calculators use — loans, health screens, paint orders and land measurement.
Finance · 2026-09-14Why Your First EMI Is Mostly InterestA reducing-balance loan front-loads interest. Here is the arithmetic behind the first year, and why prepaying early saves more than prepaying late.
Health · 2026-09-02What BMI Can and Cannot Tell YouBMI is a population screen, not a diagnosis. Where it is useful, where it misleads, and what to measure alongside it.
Home · 2026-08-21How Much Paint Does a Room Actually Need?Coverage per litre, coats, primer and the 10% you will wish you had bought — the arithmetic of a paint order.
Property · 2026-08-05Marla, Kanal and Square Feet: The 47 sq ft TrapA 10 marla plot is 2,722 sqft in Islamabad and 2,250 sqft in parts of Lahore. Here is why the same words describe different land.
Finance · 2026-10-02The EMI Formula, Explained With Real NumbersThe exact EMI formula, a worked example on a 1,000,000 loan at 18%, and why the first year is almost all interest.
Math · 2026-09-27Percentage Increase and Decrease: The Formula That Trips EveryoneHow to calculate percentage increase and decrease correctly, why a 25% rise and a 25% fall do not cancel out, and the margin vs markup trap.
Tax · 2026-09-20GST Calculation: Adding, Removing and Why Division Is Not SubtractionHow to add GST to a price and how to extract it from an inclusive total — the divide-by-1.18 rule, with worked examples.
Health · 2026-09-11BMI Formula: What the Number Means and Where It FailsThe BMI formula in metric and imperial units, the WHO categories, and the three situations where BMI gives a misleading answer.
Health · 2026-09-05How Calories Are Calculated: Mifflin-St Jeor, ExplainedThe Mifflin-St Jeor equation for BMR, the activity multipliers that turn it into daily calories, and why the multiplier is where most estimates go wrong.
Reference · 2026-08-30Unit Conversion Mistakes That Cost Real MoneyThe five unit conversions that go wrong most often, the exact factors, and how a single factor-of-two error doubles a material order.