Averages

Weighted Average vs. Average: What Is the Difference?

Compare arithmetic and weighted averages, choose the correct method, and avoid treating unequal contributions as equal.

10 min read · Practical examplesFractions

Improper Fractions and Mixed Numbers Explained

Convert between improper fractions and mixed numbers, simplify results, and understand when each form is useful.

10 min read · Practical examplesRatios

Ratio vs. Proportion: Definitions and Examples

Learn how ratios compare quantities, how proportions equate ratios, and when cross-multiplication applies.

10 min read · Practical examplesFactors and multiples

The Euclidean Algorithm Explained Step by Step

Find the greatest common factor efficiently using repeated division and remainders.

10 min read · Practical examplesFractions

How to Find the Least Common Denominator Using LCM

Use the least common multiple of denominators to add, subtract, and compare fractions efficiently.

10 min read · Practical examplesDecimals

How to Convert Decimals to Fractions

Turn terminating decimals into exact simplified fractions using place value and greatest common factors.

10 min read · Practical examplesRatios

Direct Proportion: Formula and Real-World Examples

Recognize direct proportional relationships, solve missing values, and distinguish them from nonlinear patterns.

10 min read · Practical examplesNumber theory

Prime vs. Composite Numbers

Distinguish primes, composites, units, and factors with clear definitions and divisibility examples.

10 min read · Practical examplesTrigonometry

Degrees vs. Radians in Trigonometry

Understand angle units, convert between degrees and radians, and select the correct scientific-calculator mode.

10 min read · Practical examplesDates and time

How to Calculate Time Duration Across Midnight

Find elapsed time when an interval crosses midnight, multiple dates, or a daylight-saving clock change.

10 min read · Practical examples