Things You Never Noticed VII: Wait, This Isnt the MitD Thread?

[b_jonas]

Grey_Wolf: one commenter in this thread just gave 4 times the real volume for the cylinder, another commenter offered a cone that's two inches wide on its wider side as a shape that's no wider than one inch. Most people couldn't do the calculations that you mention anyway. I'm not saying that Americans are stupid or that their educations are bad, most Europeans who grew up here with the metric system also can't do those calculations, and will commit stupid mistakes.

I don't think uses inches makes it that much weird. I can remember that an inch is 0.0254 meters, a foot is 0.305 meters, and an ounce is usually either 0.028 liters or 0.028 kilograms, and can do calculations in my head with them, and the people who have to do these calculations and actually live in a place where they have to use these units are even more familiar with them. Most calculations aren't as simple as the ones you've picked, and you'll have to remember similar arbitrary constants for them anyway. In practice, I have to remember that my handspan is 0.023 meters long and a credit card is almost 0.10 meter long and an A4 paper is 0.279 meter times 0.210 meters long, because these are the ones I actually use for measuring distances because they're faster than getting a centimeter scale, even though I actually carry a centimeter scale in my backpack. I also have to remember approximately how much real money euros, US dollars, british pounds, swedish crowns are worth in real money (and ideal canadian dollars and australian dollars too, because some far east sellers use those on ebay), and those conversions even keep changing. Heck, I have to do conversions of time units and I'm supposed to know the numeric values for all the month names, and I make mistakes with the latter ones all the time, especially for August. The arbitrary constants that I need for eyeballing calculations aren't much better than what Americans need with their units.