Question

Hi I need help on a few problems. I have been trying to do them but I can't seem to get the correct answer.

1. A population P is initially 2000. Find an exponential model (growth or decay) for the population after t years if the population P is increases by 400% every 3 years. (Round your terms to two decimal places.)

P(t)= ?


2. A population P is initially 2000. Find an exponential model (growth or decay) for the population after t years if the population P is multiplied by 0.85 every month. (Round your terms to four decimal places.)

P(t)= ???

Answer 1

For #1, you're using the formula

A = P(1+r)^(t/k)

where

A = final population at time t
P = initial population
r = growth rate (in decimal form)
t = time in years
k = frequency when the population increases

So in this case

A = unknown
P = 2000
r = 4 (400% = 4)
t = unknown
k = 3 (the frequency is every 3 years)

Answer 2

does that help?