Welcome to Percent Foundations for Everyday Life! This is the very first lesson of the course, and we are glad to have you here. Over the coming lessons, we will build a strong, practical understanding of percentages — one of the most commonly used math ideas in adult life. By the end of this lesson, we will be comfortable explaining what a percentage means and reading percentages in places like weather apps, clothing tags, and food labels.
Before we look at real-world examples, let's make sure we share a clear picture of what "percent" actually means. The word percent comes from the Latin phrase per centum, which translates to "for every hundred." So whenever we see a number followed by the % symbol, it tells us a quantity out of 100.
Think of it this way: imagine slicing something into 100 equal pieces. A percentage tells us how many of those pieces we are talking about. Writing is the same as saying "25 out of 100," which we can also express as:
