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Blog & study guides

Math explained, step by step

Worked examples and plain-English explanations. Every guide links to a calculator, so you can try the method on your own numbers.

Number senseHow to Find the LCM and GCF: 3 Methods with ExamplesListing, prime factors and Euclid's algorithm, with worked examples and when to use each method.October 19, 2026 · 6 min read FractionsHow to Convert a Fraction to a Decimal and a PercentLong division step by step, how to spot repeating decimals before you start, and a table of common fractions.October 19, 2026 · 5 min read Number senseHow to Tell if a Number Is Prime: The Square-Root RuleThe square-root rule, quick divisibility checks and worked examples like 211 and 221.October 19, 2026 · 5 min read AlgebraThe Quadratic Formula: How to Solve ax² + bx + c = 0Worked examples for two roots, one root and complex roots, what the discriminant tells you, and the mistakes to avoid.October 19, 2026 · 6 min read StatisticsMean, Median or Mode: Which Average Should You Use?How to calculate each average, why outliers change the answer, and a quick guide to choosing the right one.October 19, 2026 · 5 min read MoneySimple vs Compound Interest: How Money Really GrowsThe two formulas side by side, a 10-year comparison, how compounding frequency matters and the rule of 72.October 19, 2026 · 5 min read