How-To Guides
Step-by-step guides that teach you how to perform calculations manually.
How to Calculate Quartiles and IQR: Step-by-Step Guide
Learn to manually calculate quartiles (Q1, Q2, Q3) and the Interquartile Range (IQR) with formulas, a worked example, and common pitfalls.
Read guideHow to Calculate the Arithmetic Mean (Average): Step-by-Step Guide
Learn to calculate the arithmetic mean of a dataset manually. Understand the formula, worked examples, and common pitfalls. Essential for data analysis.
Read guideHow to Calculate Your Test Grade: Step-by-Step Guide
Learn to manually calculate your test percentage and letter grade using a simple formula. Understand inputs, common pitfalls, and a worked example.
Read guideHow to Calculate a Confidence Interval for the Population Mean: Step-by-Step Guide
Learn to manually calculate confidence intervals for population means. This guide covers formulas, step-by-step examples, common pitfalls, and interpretation for engineers and STEM professionals.
Read guideHow to Calculate Standard Deviation: Step-by-Step Guide
Learn to manually calculate standard deviation and variance. Understand the formula, steps, and interpretation with a worked example.
Read guideHow to Calculate Mean, Median, and Mode: Step-by-Step Guide
Learn to manually calculate the mean, median, and mode of any dataset with this detailed step-by-step guide, including formulas, examples, and common pitfalls.
Read guideHow to Calculate Basic Statistics Manually: Mean, Median, Mode, Standard Deviation
Learn to manually calculate mean, median, mode, and standard deviation with formulas, examples, and common pitfalls. Understand core statistical concepts.
Read guideHow to Calculate Tax and Tip Combined: Step-by-Step Guide
Master combined tax and tip calculations for any bill. Learn the manual formula, follow a detailed example, identify common errors, and optimize your spending.
Read guideHow to Calculate Mark-Up: Step-by-Step Guide
Learn to manually calculate selling price, gross profit, and profit margin from cost and markup percentage. Master the formulas with a step-by-step guide and example.
Read guideHow to Calculate Reverse Percentage: Step-by-Step Guide
Learn to calculate reverse percentage manually. Find the original value after a percentage change using formulas, worked examples, and common pitfalls.
Read guideHow to Calculate Percentage Off: Step-by-Step Guide
Learn to manually calculate percentage off with our precise guide. Understand the formula, follow a worked example, and avoid common pitfalls.
Read guideHow to Calculate Percentage Error: Step-by-Step Guide
Learn to calculate percentage error by hand using the formula. Includes a worked example, common pitfalls, and when to use a calculator.
Read guideHow to Calculate Discount: Step-by-Step Guide
Learn to manually calculate discounts and final prices. Master the formulas, follow a worked example, and avoid common errors. Essential for smart shopping.
Read guideHow to Calculate Tip: Step-by-Step Guide
Learn to manually calculate restaurant tips. Understand the formula, common percentages, and how to determine total bill and tip per person. Includes example.
Read guideHow to Convert Decimal to Percent: Step-by-Step Guide
Convert decimals to percentages manually
Read guideHow to Convert Percent to Decimal: Step-by-Step Guide
Convert percent to decimal manually
Read guideHow to Calculate Percentage Decrease: Step-by-Step Guide
Learn to calculate percentage decrease manually
Read guideHow to Calculate Percentage Increase: Step-by-Step Guide
Calculate percent growth manually
Read guideHow to Calculate Percent: Step-by-Step Guide
Learn to calculate percent manually
Read guideHow to Calculate Function Composition: Step-by-Step Guide
Manual calculation of (f∘g)(x)
Read guidePolynomial Long Division: A Step-by-Step Guide
Divide polynomials by hand
Read guideHow to Apply Descartes' Rule of Signs: Step-by-Step Guide
Determine positive and negative real roots
Read guideHow to Calculate Hyperbola Properties: Step-by-Step Guide
Calculate hyperbola properties manually
Read guideHow to Calculate Prime Factorisation: Step-by-Step Guide
Learn to find prime factors manually
Read guideHow to Calculate Rational Roots Using the Rational Root Theorem: Step-by-Step Guide
Learn to manually find all possible rational roots of a polynomial using the Rational Root Theorem. Includes formula, examples, and common pitfalls.
Read guideHow to Perform Synthetic Division: Step-by-Step Guide
Learn to manually perform synthetic division to divide polynomials by linear factors. This guide covers setup, iterative calculations, interpreting results, and common pitfalls.
Read guideHow to Calculate the Discriminant: Step-by-Step Guide
Learn to manually calculate the discriminant (Δ = b²−4ac) of a quadratic equation. Understand its formula, interpret roots, and avoid common errors.
Read guideHow to Solve Quadratic Equations by Completing the Square: Step-by-Step Guide
Learn to solve quadratic equations by completing the square. Transform standard form to vertex form manually with a detailed example and common pitfalls.
Read guideHow to Calculate the Digital Root: Step-by-Step Guide
Learn to manually calculate the digital root of any positive integer. Understand the iterative summation process and the modulo 9 formula.
Read guideHow to Calculate the Sum of Digits: Step-by-Step Guide
Learn to manually calculate the sum of digits for any integer. Understand the formula, digital root, and divisibility checks with a step-by-step guide and example.
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