Question 1206141
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Assume there is a certain population of fish in a pond whose growth is described by the logistic equation. 
It is estimated that the carrying capacity for the pond is 1600 fish. Absent constraints, 
the population would grow by 120% per year.

If the starting population is given by p0=200, then estimate population of fish in the pond 
after one and two years.
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One good Internet source to read and to learn about a logistic equation is Libre text
https://math.libretexts.org/Bookshelves/Calculus/Calculus_(OpenStax)/08%3A_Introduction_to_Differential_Equations/8.04%3A_The_Logistic_Equation



<pre>
The general solution for the standard logistic differential equation is so called logistic function

    P(t) = {{{(P[0]*K*e^(rt))/((K-P[0])+P[0]*e^(rt))}}}.


Here {{{P[0]}}} is the initial population, P(t) is current population, K is the carrying capacity 
and "r" is growth rate. Number "e" = 2.71828 is the base of natural logarithm 
(shown here as an approximate value).


In this current problem in the post, we are given

    {{{P[0]}}} = 200,  K = 1600,  r = 1.2.


They want you determine P(1) and P(2), the population after 1 and 2 years.


(a)  For t = 1 year

     P(1) = {{{(200*1600*e^(1.2*1))/((1600-200)+200*e^(1.2*1))}}} = 514.74,  or 514  (rounded).


(b)  For t = 2 years

     P(2) = {{{(200*1600*e^(1.2*2))/((1600-200)+200*e^(1.2*2))}}} = 978.58,  or  979  (rounded).
</pre>

Solved.


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Post-solution notice

<pre>
    In my opinion, the question in the post is posed/worded INCORRECTLY.

    It asks about the breeding season, but we are not given information
    for a breading season - we are given information, related to years - so,
    the question should be about the times of years, not the breeding seasons.

    The life of fish includes not only breeding - it includes also struggle for food, 
    survival from predators and diseases, natural death, that is, processes with a period of a year.
</pre>