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The population of Arlington, Texas on January 1st 2007 was approximately 369,690. (Extrapolated from a 2000 US census population of 332,969 and a population of 365,438 in 2007.)
The population of Austin, Texas on January 1st 2007 was approximately 770,759. (Extrapolated from a 2000 US census population of 656,562 and a population of 786,386 in 2009.)