Definition of a percent
Pre-algebra students in OpenStax Prealgebra 2E learn that a percent is a ratio with a denominator of 100, making it a special type of fraction. The word percent comes from Latin, literally meaning per hundred. So 57% means 57 out of 100, written as the fraction 57/100. One hundred percent equals 100/100 = 1 whole. Understanding percent as a ratio-out-of-100 makes converting between percents, fractions, and decimals intuitive and connects to real-world uses in finance, statistics, and measurement.
Key Concepts
Property A percent is a ratio whose denominator is 100.
Examples 57 out of 100 students is 57%, which is the ratio $\frac{57}{100}$.
25% means a ratio of $\frac{25}{100}$.
Common Questions
What is the definition of a percent?
A percent is a ratio whose denominator is 100. It expresses how many out of every hundred.
What does 57% mean as a fraction?
57% means 57 out of 100, written as 57/100.
What does 100% represent?
100% is the ratio 100/100, which equals 1 whole. It represents the entire amount.
What does the word percent literally mean?
Percent comes from the Latin phrase per centum, meaning per one hundred.
How do you convert a percent to a decimal?
Divide the percent number by 100 (or move the decimal point two places to the left). For example, 57% = 0.57.