SOLUTION: . A city population of 170,000 grows continuously according to the model P = 170000e0.0285t where P is the population t years after the year 2000. In what year does the population

Algebra ->  Exponential-and-logarithmic-functions -> SOLUTION: . A city population of 170,000 grows continuously according to the model P = 170000e0.0285t where P is the population t years after the year 2000. In what year does the population      Log On


   



Question 1178994: . A city population of 170,000 grows continuously according to the model P = 170000e0.0285t
where P is the population t years after the year 2000. In what year does the population reach
250000?

Answer by ikleyn(52802) About Me  (Show Source):
You can put this solution on YOUR website!
.
A city population of 170,000 grows continuously according to the model P = 170000e0.0285t
where P is the population t years after the year 2000. In what year does the population reach 250000?
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Your exponential formula for the population growth is


    P(t) = 170000%2Ae%5E%280.0285%2At%29.


Based on the condition, you write the equation for t as you read your text


    250000 = 17000%2Ae%5E%280.0285%2At%29.


Next, you divide both sides by 170000


    250000%2F170000 = e%5E%280.0285%2At%29,    or


    1.470 = e%5E%280.0285%2At%29.


Now, you take natural logarithm of both sides


    ln(1.470) = 0.0285*t


which gives you an expression for time "t"


    t = ln%281.470%29%2F0.0285


Next you use your calculator and get


    t = 13.518  years   (rouned)      ANSWER


ANSWER.  13 years and  189 days.

Solved, answered, explained and completed.

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To see many other solved problems on exponential growth/decay,  look into the lessons
    - Population growth problems
    - Radioactive decay problems
    - Carbon dating problems
    - Bacteria growth problems
    - A medication decay in a human's body
    - Problems on appreciated/depreciated values
    - Inflation and Salary problems
in this site.


Also,  you have this free of charge online textbook in ALGEBRA-I in this site
    - ALGEBRA-I - YOUR ONLINE TEXTBOOK.

The referred lessons are the part of this online textbook under the topic "Logarithms".


Save the link to this online textbook together with its description

Free of charge online textbook in ALGEBRA-I
https://www.algebra.com/algebra/homework/quadratic/lessons/ALGEBRA-I-YOUR-ONLINE-TEXTBOOK.lesson

to your archive and use it when it is needed.


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