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the population of a town is decreasing at a rate of 1.8% per year. The current population of the own in 12000.

a)write and equation that models the population of the town
b)how long will it take for the population to decline to one quarter of its current population?
c)calculate the approx. instantaneuos rate of change at 5 years.

a) I would write
P(n) = 12000(.982)^n where n is the number of years from the present

for b)

solve .25 = (.982)^n

I assume you know how to do logs.

c) have we established if you know Calculus?
That will determine how to answer that.

nope i don't, the school makes it manditory to take advanced functions before calculus

in that case I would take something like

(P(5.01) - P(5))/(5.01 - 5)
= -199

so at the 5 year point, the population is decreasing at appr 200 people/year

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