Percentage Calculations: Three Common Mistakes
Check the starting value before calculating a discount, an increase, or a percentage of a total.
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Clear methods, practical examples, and the details that make a calculation more useful.
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How to Estimate the Cost of a Car Trip
Use distance, fuel economy, and your own fuel price to estimate a trip cost.
Read articleScreen Size in Inches: What It Really Measures
A screen size is a diagonal measurement. Convert it to centimeters and check the actual width and height.
Read articleHow to Count Days and Weeks Correctly
Inclusive dates, elapsed time, and ISO weeks: understand which convention your calculation uses.
Read articleQR Codes and Passwords: What to Check Before Sharing
Check what a QR code contains and how a password tool handles your data before sharing.
Read articleFrench Property Prices: How to Read a DVF Median
Understand the period, sample size, and limitations behind a French property price median.
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