Wolfram | Alpha: Acres per square mile? (oddities)

*To*: mathgroup at smc.vnet.net*Subject*: [mg101146] Wolfram | Alpha: Acres per square mile? (oddities)*From*: AES <siegman at stanford.edu>*Date*: Thu, 25 Jun 2009 07:13:04 -0400 (EDT)*Organization*: Stanford University

Just out of curiosity (and a current need for info) (and to start learning about W|A), typed: Acres per square mile into Wolfram | Alpha. Results came back (had to do a little hand editing of the following): Assuming U.S. acres for "acres" Use international acres commercial acres Irish acres Hungarian acres instead Input interpretation: acres/mi^2 Unit conversions: 0.3861 acres per square kilometer 6.323 square meters per acre 0.1563 hectares per square kilometer 0.4047 hectares per square mile 0.003861 acres per hectare Don't see "640" there anywhere! -- and something seriously wrong with that first unit conversion? (not to mention all the others) -- or at least the way it's phrased -- more like 250 acres per square kilometer? Went to M7, tried Needs["Units`"] Convert[Acre, Mile^2] Mile^2/640 Went to Units Tutorial: Seems odd to see "Centimeter", "Meter", "Micron", "Mile", and a bunch of arcane units listed there -- but NOT "Kilometer"??? ("Gram" and "Kilogram" are in there).