Do you buy gravel by the cubic mile then? Weird real-life unit conversions come up all the time, often when you need to calculate a net weight or price, and yo

Do you buy gravel by the cubic mile then? Weird real-life unit conversions come up all the time, often when you need to calculate a net weight or price, and you have some big surface area (eg. a road, with width in yards + feet, thickness in inches, and length in miles), and your gravel supplier prices by ton, and you look up the density in a conversion table and see something like lbs/ft^3, and now you have a whole bunch of opportunities to make a mistake.