The so-called "imperial" system of weights and measures was formulated over centuries of "practical application" before the advent of "mass" education and the understanding and application of "higher" maths etc.
For centuries the usage by the "common person" of weights and measures was conducted by a largely "illiterate" population so that weights and measurements had to be something that all could understand on a practical level.
For example the inch related to the distance between the tip of the finger to the first knuckle of the second finger of an average sized man (average then being approx 5'6-7' in height). Similarly the foot was an average sized mans foot from heel to longest toe. The yard was the average "stride" taken by an average man. It so happened that the ratio of 12 inches relates very closely to one average sized foot and three feet similarly to one yard. An average sized man could pace out one mile with 1,760 paces (or 5280feet, although the mile was previously set arbitrarily by the monarchy as a means of determining incremental distances for land tenure) and so forth etc, it was a system that everyone could understand and "carry around” with them at all times. Mathematics, as we understand it today was never a requirement for day-to-day life for the vast majority.
The metre on the other hand was a "theoretical" distance promoted by the French based on the division of a distance that, as history has determined, they got wrong in the first place, and because the French could not "get their heads" around anything very complicated, they divide or multiplied everything by the number 10.