Understanding Basic Percentages

A percentage represents a fraction with a denominator of 100. The term comes from the Latin 'per centum' meaning 'by the hundred'. It's a way to express proportions and comparisons in a standardized format.

Percentages are everywhere: in discounts, finance, statistics, and even in health-related metrics like body fat and dehydration levels. They help quantify changes and can make complex data more relatable.

To calculate a percentage increase, subtract the original number from the new number. Then, divide this result by the original number and multiply by 100. The final figure is your percentage increase.

Percentage decrease is found similarly to increase, but by starting with the difference between the original and the lower number. This reflects reductions, such as price drops or efficiency savings.

Percentages can exceed 100. This occurs when the comparative value is more than the reference point. For example, a 200% increase implies the final amount is triple the original value.

In probability, percentages are used to express the likelihood of an event occurring. A 50% chance means the event is as likely to happen as not - akin to the flip of a fair coin.

The concept of percent can extend into surprising domains, such as the 'percent error' in scientific measurements or 'percentage points' when discussing the difference between two percentages, crucial in finance and statistics.

The percent symbol (%) was initially written as 'per 100' or 'pc'. It evolved over centuries into the familiar sign we use today.