7. Population decay. Since 1990, the population of Gary, Indiana, has been decreasing by 1.87% per year. The rate of change of the city's population P, t years after 1990, is given by dP- -0.0187P. dt a. In 1990, the population of Gary was 116,646. (Source: U.S. Census Bureau.) Find an exponential function that models this situation. b. Estimate the population of Gary in 2025.

7. Population decay. Since 1990, the population of Gary, Indiana, has been decreasing by 1.87% per year. The rate of change of the city's population P, t years after 1990, is given by dP- -0.0187P. dt a. In 1990, the population of Gary was 116,646. (Source: U.S. Census Bureau.) Find an exponential function that models this situation. b. Estimate the population of Gary in 2025.

College Algebra

7th Edition

ISBN:9781305115545

Author:James Stewart, Lothar Redlin, Saleem Watson

Publisher:James Stewart, Lothar Redlin, Saleem Watson

Chapter4: Exponential And Logarithmic Functions

Section: Chapter Questions

Problem 12CC: Suppose that the initial size of a population is n0 and the population grows exponentially. Let n(t)...

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Suppose that the initial size of a population is n0 and the population grows exponentially. Let n(t) be the size of the population at time t. (a) Write a formula for n(t) in terms of the doubling time a. (b) Write a formula for n(t) in terms of the relative growth rate r.
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