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The population of a colony of rabbits grows exponentially. The colony begins with 18 rabbits; five years later there are 300 rabbits.

a) Give a formula for the population of the colony of rabbits as a function of time in years.
b) Estimate how long it takes for the population of the colony to reach 2000 rabbits.

1 Answer

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Answer:

a) Let P(t) be the population of the colony at time t in years. Since the population grows exponentially, we can model the population with the formula P(t) = P0e^kt, where P0 is the initial population (when t=0), and k is a constant. We know that the colony begins with 18 rabbits, so P0 = 18. We also know that five years later, the population is 300, so P(5) = 300. Plugging in these values, we get:

300 = 18e^(5k)

Dividing both sides by 18 and taking the natural logarithm of both sides, we get:

ln(300/18) = 5k

Simplifying, we get:

k = ln(300/18) / 5

So the formula for the population of the colony is:

P(t) = 18e^(t*ln(300/18)/5)

b) To estimate how long it takes for the population to reach 2000 rabbits, we need to solve for t in the equation P(t) = 2000. Plugging in the formula from part (a), we get:

2000 = 18e^(t*ln(300/18)/5)

Dividing both sides by 18 and taking the natural logarithm of both sides, we get:

ln(2000/18) = t*ln(300/18)/5

Simplifying, we get:

t = 5*ln(2000/18) / ln(300/18)

Using a calculator, we get:

t ≈ 23.7 years

So it will take about 23.7 years for the population to reach 2000 rabbits.

Explanation:

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