Family story: Supposedly, some uncle or some such of mine owned land and at some point some large company wanted to buy the mineral rights. They offered him like $9/acre or whatever and he said "Make it $10 and you have a deal." His reason for wanting $10 was to simplify the math: X acres times 10 = just add a zero to the number of acres.

He wasn't comfortable with math, but supposedly he made quite good money.