percentagens

A percentage is a way to express a number as a fraction of 100. It is written with the symbol %. For example, 25% equals 25 out of 100, which is the decimal 0.25 or the fraction 25/100.

Converting between representations: percentage to decimal is divide by 100; decimal to percentage multiply by 100; fraction to percentage multiply by 100. Example: 3/8 = 0.375 = 37.5%. To find a percentage of a value: (percentage/100) × total. Example: 15% of 200 = 0.15 × 200 = 30. To calculate percent change: ((new - old) / old) × 100%.

Percentage points and relative change: A change of 1 percentage point is an absolute difference of 1% (0.01 in decimal). It is not the same as a 1% relative change. For example, 20% to 21% is a 1 percentage point increase, but a 5% relative increase.

Applications and history: Percentages are used in finance, statistics, demographics, education, pricing, taxation, and many everyday calculations. The term comes from Latin per centum; the modern percent sign originated in early modern Europe and became common with the growth of commercial arithmetic.