I agree that base 10 is not optimal but the US/imperial distance system is hard to defend. A foot is 12 inches, a yard is 3 feet and a mile is 1760 yards. And

I agree that base 10 is not optimal but the US/imperial distance system is hard to defend. A foot is 12 inches, a yard is 3 feet and a mile is 1760 yards. And don't get me started on the weight and volume units. I entertain a hypothesis that such inconsistent unit systems (and heavy usage of fractions instead of decimal or other positional system) do make people less apt in handling numbers. Having lived for a while in England (which is legally metric but in practice imperial for many things) for a while, I think it is reflected in how things involving numbers are often stated in quite convoluted terms.