➗ Math guides
Percentages, ratios and quick calculations.
How to Find a Square Root (and What It Really Means)
What a square root is, how to estimate one by hand, and the difference between square roots and cube roots — with worked examples and a calculator.
28 September 2026 · 3 min read
How to Calculate Percentage Change (Increase and Decrease)
Work out the percentage increase or decrease between two numbers, why the original value is the anchor, and how percentage change differs from percentage points.
21 September 2026 · 2 min read
How to Add, Subtract, Multiply and Divide Fractions
A clear, worked guide to the four fraction operations — common denominators, cross-multiplying, flipping to divide — plus how to simplify and convert to mixed numbers.
14 September 2026 · 2 min read
How Much Should You Tip? A Practical Guide
Tipping rules change by country and situation. Learn the standard percentages for restaurants, bars, taxis and delivery, how to work a tip out in your head, and how to split a bill fairly.
28 August 2026 · 2 min read
How GPA Is Calculated: Weighted vs Unweighted
Your grade point average turns letter grades into a single number on a 4.0 scale. Learn how GPA is calculated, the difference between weighted and unweighted, and how credit hours change the result.
26 August 2026 · 2 min read
How to Calculate a Discount (Including Stacked Deals)
Working out a sale price is simple for one discount and sneaky for two. Learn how to calculate a percentage off, why stacked discounts don't add up, and how to find the original price.
24 August 2026 · 2 min read
Percentages Made Simple: Three Formulas That Cover Everything
Almost every percentage question is one of three types. Learn the three formulas — percentage of a number, one number as a percentage of another, and percentage change — with worked examples.
12 June 2026 · 2 min read