Mathematical and Technological Literacy I Worksheet 2a:  Exponential Modeling

Exponential Modeling

1.  U.S. Population Growth – The 2000 census found a U.S. population of about 281 million.  Write an equation for the U.S. population that assumes exponential growth at 0.7% per year. 

 a.      Use the equation to predict the U.S. population in 2100. 

 b.      Use Excel to predict the U.S. population in 2100.

2.  Human vs Black Bear Population - The New York Times reported that wildlife biologists have found a direct link between the increase in the human population in Florida and the decline of the local black bear population.  From 1953 to 1993, the human population increased, on average, at a rate of 8% per year, while the black bear population decreased at a rate of 6% per year.  In 1953 the black bear population was 11,000.   In 1993 the human population of Florida was 13 million. 

a.      Find the black bear population for 1993.

b.      If this trend continues, when will the black bear population be less than 100?

c.      If the human population trend continues, how long will it take the human population to double? 

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