Everyday Math & Text
How to Figure Discounts, Sales Tax and Tips in Your Head
One trick covers most shopping math: find 10% first. Here's how to price discounts, add sales tax and pick a tip in your head, and why stacked discounts mislead.
Posts tagged “Percentages”
Everyday Math & Text
Percent Change vs Percentage Points
A rate going from 4% to 5% rose by 1 percentage point, or by 25%. Here's how to calculate each, when to use which, and the mistakes that make numbers misleading.