An Urban Density Model Is a Formula That Relates the Population

question 21

Multiple Choice

An urban density model is a formula that relates the population density D ( in thousands/ mi ² ) to the distance x (in miles) from the center of the city. The formula for the central density a and coefficient of decay b has been found to be appropriate for many large U.S. cities. For the city of Atlanta in 1970, a = 5.5 and b = 0.10. At approximately what distance was the population density 1,800 per square mile?

• A)13.5 mi
• B)11.2 mi
• C)57.9 mi
• D)4.9 mi
• E)23.5 mi

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