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88-BC43) Bacteria in a certain culture increase at a rate proportional to the number present. If the number of bacteria doubles in three hours, in how many hours will the number of bacteria triple

User Gaurav Navgire
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Final answer:

To find the time it will take for the number of bacteria to triple, we use the concept of exponential growth. The number of bacteria in the culture is increasing at a rate proportional to the number present. By setting up a proportional relationship and solving for time, we find that it will take approximately 4.807 hours for the number of bacteria to triple.

Step-by-step explanation:

To solve this problem, we need to use the concept of exponential growth. The number of bacteria in the culture is increasing at a rate proportional to the number present. If the number of bacteria doubles in three hours, we can set up a proportional relationship as follows:

Let N(t) represent the number of bacteria at time t.

N(t) = N(0)e^rt

Where N(0) is the initial number of bacteria, e is the base of natural logarithm (approximately 2.71828), r is the growth rate, and t is the time in hours.

Since the number of bacteria doubles in three hours, we can plug in the given information to solve for r as follows:

2N(0) = N(0)e^(3r)

2 = e^(3r)

Take the natural logarithm of both sides:

ln(2) = 3r

Now we can solve for r:

r = ln(2)/3

Finally, to find the time it will take for the number of bacteria to triple, we substitute r into the equation:

N(t) = N(0)e^(rt)

3N(0) = N(0)e^(ln(2)/3 * t)

3 = e^(ln(2)/3 * t)

Take the natural logarithm of both sides again:

ln(3) = ln(2)/3 * t

Solve for t:

t = 3 * ln(3) / ln(2)

User Pruthviraj
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