320/400 = 80%
A value like 320 out of 400, or 80%, shows up in everyday life in places like test scores, survey results, store discounts, and sports statistics. For example, getting 320 points out of 400 on a project means most of the work was completed successfully.
You can picture 80% as four-fifths of a whole, leaving about one-fifth unfinished or missing. On a 100-square grid, it would look like 80 shaded squares, which is clearly more than three-quarters but less than the whole.
A common mistake is treating 80% as if it means 80 points out of every possible total. The actual number of points depends on the total, so 80% of 400 and 80% of 50 represent the same proportion but different amounts.
