SOLUTION: Can someone please assist me in setting this equation up and explain why I am doing it in such a way... please? A lake is stocked with a certain species of fish, the fish populati

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Question 953045: Can someone please assist me in setting this equation up and explain why I am doing it in such a way... please?
A lake is stocked with a certain species of fish, the fish population is modeled by the function p=700/e^-0.8t
where P is the number of fish in thousands and t is measured in years since the lake was stocked
Find the fish population after 2 years?
After how many years will the fish population be 250000 fish?
THanks!
Answer by ankor@dixie-net.com(22740) (Show Source):
You can put this solution on YOUR website!
A lake is stocked with a certain species of fish,
the fish population is modeled by the function
where P is the number of fish in thousands
and t is measured in years since the lake was stocked
:
Find the fish population after 2 years?
t = 2,so we have

find e^-1.6 on your calc

p = 3,467 fish after 2 yrs
:
After how many years will the fish population be 250000 fish?
Write this as
250000 =
multiply both sides by e^(-.8t)

divide both sides by 250000

find the nat log of both sides

the log equiv of exponents, find the ln of .0028
-.8t*ln(e) = -5.878
the ln of e is 1 so we can just write
-.8t = -5.878
t =
t = 7.35 years to increase to 250000 fish
:
:
did I explain well enough so you know what'sgoing on here? ankor@att.net