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If the number of bacteria in a colony doubles every 72 hours and there is currently a population of 105,700 bacteria, what will the population be 216 hours from now? bacteria

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EXPLANATION

Let's see the facts:

Period = 72 hours

Initial Population= 105,700

Time = 216 hours

The equation is as follows:


P=P_0e^(rt)^{}

P_0=Initial Population

r= rate of growth

t=time

First, we need to find r:

In 72 hours ------> 2*105,700 = 211,400 bacteria

Replacing terms:


211,400=105,700e^((r72))

Dividing both sides by 105,700:


(211,400)/(105,700)=e^((72r))

Applying ln to both sides:


\ln ((211,400)/(105,700))=\ln (e^(72r))

Simplifying:


\ln ((211,400)/(105,700))=72r\cdot\ln e

Dividing both sides by 72:


(\ln ((211,400)/(105,700)))/(72)=r

Switching sides:


r=(\ln ((2114)/(1057)))/(72)

Simplifying:


r=(0.69)/(72)=0.009627

Now that we have r=0.009627 we can calculate the value of P as shown as follows:


P=105,700e^((0.009627\cdot216))

Multiplying terms:


P=105,700\cdot e^((2.08))^{}

Now, we can solve the expression:


P=105,700\cdot8=845,600

The answer is 845,600 bacteria.

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