education
Jul 25, 2026
How to Calculate Percentages in Your Head (and When to Use a Calculator)
Three mental-math tricks that cover 90% of everyday percentage problems — plus when the shortcuts stop working.
Explanations of foundational concepts — percentages, BMI, unit conversion — built to be remembered.
Three mental-math tricks that cover 90% of everyday percentage problems — plus when the shortcuts stop working.
BMI is a useful screening number with real limits. Learn what it says, what it hides, and how to read it honestly.