Proportions & Ratios Blog
Free guides to ratios and proportions: cross-multiplication, direct vs inverse proportion, map scales, recipes, dilutions and finance, with worked examples.
Showing 1–9 of 9 posts
Proportions in Finance: Interest, Currency & Tax Ratios
Use proportions to calculate simple interest, compare loans, convert currency, split a portfolio, find ROI and work out sales tax, step by step.
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Proportions in Architecture: Scale Drawings & Golden Ratio
How architects use proportions: reading 1:50 blueprints, the golden ratio (1:1.618), material scaling, concrete mix ratios and scale models, with examples.
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How to Scale a Recipe Using Proportions (Easy Method)
Scale any recipe with one proportion: divide new servings by original servings, then multiply every ingredient. Worked examples and a conversion table.
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Cross-Multiplication: How to Solve Proportions in 3 Steps
Cross-multiplication turns a/b = c/d into a × d = b × c. See why it works, how to solve for x in any position, decimal examples, and the mistakes to avoid.
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What Is a Proportion? Definition, Formula & Examples
A proportion is an equation saying two ratios are equal (a/b = c/d). Learn the definition, the cross-multiplication formula, how to solve for x and examples.
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Proportions in Chemistry: Dilutions (C1V1=C2V2) & Moles
How chemists use proportions for dilutions (C1V1 = C2V2), mole ratios in stoichiometry and weight-based dosing — with clear, step-by-step worked examples.
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Map Scale: How to Convert Map Distance to Real Distance
How map scales work and how to convert map distance to real distance with a proportion. Step-by-step examples for ratio scales, blueprints and models.
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Direct vs Inverse Proportion: Formulas, Examples & Test
Direct proportion keeps y/x constant (y = kx); inverse keeps x·y constant (xy = k). Learn the difference with a quick test, a table and worked examples.
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10 Everyday Uses of Proportions (With Worked Examples)
Recipes, tips, unit conversions, fuel range, photo resizing, dosages and currency: 10 everyday problems solved with a simple proportion, math shown.
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