The number of bacteria in a certain population increases according to a continuous exponential growth model, with a growth rate parameter of 4.3% per hour. How many hours does it take for the size of the sample to double? Note this is a continuous exponential growth model. Do not round any intermediate computations, and round your answer to the nearest hundredth.

Respuesta :

Answer:

16.12 hours

Explanation:

A continuous exponential growth model is given below:

[tex]P(t)=P_oe^{rt}[/tex]

• The growth rate, r = 4.3% = 0.043

,

• t = time in hours

,

• Po = Initial population

,

• P(t) = Present population

We want to find the number of hours it takes the population to double. That is if the initial population, Po = 1

• The present population, P(t) = 1 x 2 = 2.

Substitute these values into the model above to get:

[tex]2=1(e^{0.043t})[/tex]

Since natural logarithm(ln) is the inverse of exponential, take the natural logarithm of both sides to remove the exponential operator.

[tex]\begin{gathered} \ln (2)=\ln (e^{0.043t}) \\ \ln (2)=0.043t \end{gathered}[/tex]

Divide both sides by 0.043.

[tex]\begin{gathered} \frac{\ln (2)}{0.043}=\frac{0.043t}{0.043} \\ t=\frac{\ln(2)}{0.043} \\ t\approx16.12 \end{gathered}[/tex]

It will take 16.12 hours for the size of the sample to double.