Maths and percentages guides
Percentages, fractions, ratios and proportions, step by step.
14 articles
- Decimal to Fraction: Convert in Three StepsTurn any decimal into a fraction by writing it over a power of 10 and simplifying, with a chart and a method for recurring decimals like 0.333…Decimal to Fraction · 6 min read
- Fraction Calculator: Add, Subtract, Multiply, DivideAdd, subtract, multiply and divide fractions by hand with one rule for each, a worked example, a comparison table and a recipe-scaling case.Fraction · 7 min read
- Fraction to Decimal: Divide, Round and CheckConvert a fraction to a decimal by dividing the numerator by the denominator, and learn which fractions terminate, which repeat and how to round.Fraction to Decimal · 6 min read
- How to Calculate Percentage Change, Step by StepCalculate percentage change with (new − old) ÷ old × 100. See a 15% rise and a 20% fall worked out, why points differ from percent, and what to do at zero.Percentages · 6 min read
- Mixed Fraction Calculator: Convert and CalculateConvert mixed fractions to improper fractions and back, then add, subtract, multiply and divide mixed numbers with worked examples and a chart.Mixed Fraction · 7 min read
- Percentage Calculator: 4 Ways to Find a PercentA percentage calculator answers four questions: X% of a number, what percent one number is of another, the whole from a part, and a discounted price.Percentage Calculator · 6 min read
- Percentage Decrease Calculator: Price Drops Worked OutPercentage decrease = (old − new) ÷ old × 100. See ₹2,000 falling to ₹1,700 as 15%, how to find the original price, and why a 20% drop needs a 25% rise.Percentage Decrease · 6 min read
- Percentage Difference Formula and ExamplesPercentage difference compares two values by dividing their gap by their average. See the formula, a worked ₹ example and how it differs from change.Percentage Difference · 6 min read
- How to Calculate Percentage Increase (Examples)Percentage increase calculator formula, (new − old) ÷ old × 100, with a salary-hike example, how to add 15% to a price and the base mistake to avoid.Percentage Increase · 6 min read
- Proportion Calculator: Solve a/b = c/d Step by StepSolve direct and inverse proportion with cross-multiplication or the unitary method, using price, speed, map-scale and recipe examples.Proportion · 7 min read
- Ratio Calculator: Simplify and Share in a RatioSimplify a ratio with the greatest common factor, share an amount in a ratio such as 2 : 3 : 5, and convert ratios to fractions and percentages.Ratio · 6 min read
- Percentage changes made simpleLearn how to calculate percentage increase and decrease with easy examples you can use every day.Percentages · 4 min read
- Work out discounts in secondsLearn how to calculate discounts, final prices and savings with simple, step-by-step examples.Discounts · 4 min read
- Mean, median and standard deviation, explainedLearn what mean, median and standard deviation tell you about a set of numbers, with one worked data set.Statistics · 6 min read
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