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The initial population of a town is 3200 , and it grows with a doubling time of 16years. Determine how long it will take for the population to quadruple.

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The equation for determining exponential population growth is expressed as

A = Aox^(t/T)

where

A represents the population after time t

Ao represents the initial population

x represents the growth rate

t represents the time

T represents the time taken to achieve the change or doubling time

From the information given,

Ao = 3200

T = 16

x = 2 because it is doubling

A = 3200 * 4 = 12800 because quadruple means 4 times

By substituting these values into the formula, we have

12800 = 3200 * 2^(t/16)

Dividing both sides by 3200, we have

12800/3200 = 3200/3200 * 2^(t/16)

4 = 2^(t/16)

Taking natural log of both sides of the equation, we have

ln 4 = ln2^(t/16)

By applying one of the rules of logarithm, lna^b = blna, we have

ln 4 = (t/16)ln2

Dividing both sides of the equation by ln2, we have

ln4/ln2 = (t/16)ln2/ln2

2 = t/16

By crossmultiplying,

t = 16 * 2

t = 32

It will take 32 years

User Anton Petrov
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