In decimal systems one relies on multiples of 10, making it easy to convert between units and calculate with large numbers. But US customary measures and British imperial measures use either 12 or 16 as their base (for example, 12 inches in a foot and 16 ounces in a pound), which is easier for dividing things into thirds and quarters. It’s this feature that makes these systems more appropriate to market bartering and other quick calculations. Think of it like slicing up a pizza. You can quickly divide it into quarters or eighths, but how would you cut it into ten slices?
