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The number of bacteria in a culture decreases according to a continuous exponential decay model. The initial population in a study is 500 bacteria, and there are 390 bacteria left after 6 minutes. Let be the time (in minutes) since the beginning of the study, and let y be the number of bacteria at time. Write a formula relating to t Use exact expressions to fill in the missing parts of the formula.

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Final answer:

To model the exponential decay of a bacteria culture, utilize the formula y = y_0 · e^{kt}. Given an initial population of 500 and 390 remaining after 6 minutes, solve for the decay constant k using the steps provided to complete the model.

Step-by-step explanation:

To write an exponential decay formula for a population of bacteria that decreases over time, we can use the exponential decay model:

y = y_0 · e^{kt}

Where:






Given that the initial population (y_0) is 500 bacteria and there are 390 bacteria left after 6 minutes, we can calculate the decay constant k using the formula:

390 = 500 · e^{6k}

Divide both sides by 500 to get:

0.78 = e^{6k}

To solve for k, take the natural logarithm of both sides:

ln(0.78) = 6k

Then we can divide by 6 to find k.

Once we have k, we can fill it back into the original decay formula to provide a complete model for the population over time:

y = 500 · e^{kt}

This is the formula relating the number of bacteria to time t, where k is a specific constant that you will calculate based on the initial conditions provided. It allows you to predict the number of bacteria at any given time after the experiment begins.

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