Example: Evaluating an Exponential Decay Model for a Bacteria Population
To evaluate an exponential decay model, first determine the decay rate, and then apply it to find a future amount. For example, suppose a bacteria population declines from 700,000 to 400,000 in 5 hours after the administration of medication. Using the exponential decay formula , substitute the given values: . Dividing by 700,000 gives . Taking the natural logarithm of both sides results in , so the decay rate is . To find the population after 24 hours, use this rate in the formula: . Evaluating this expression yields approximately 47,700. Thus, there will be about 47,700 bacteria remaining.
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Ch.10 Exponential and Logarithmic Functions - Intermediate Algebra @ OpenStax
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A public health inspector is monitoring the effectiveness of a sanitization process in a food production facility using the exponential decay model . A sample of bacteria measured at 700,000 units was treated and found to decline to 400,000 units after 5 hours. Match each variable from the formula to its corresponding value or description from this scenario.
As a quality assurance analyst, you are monitoring the degradation of a chemical additive in a new product. The additive's concentration decays continuously from 700,000 parts per billion down to 400,000 parts per billion over a period of 5 months. Recalling the continuous exponential decay formula, , which equation shows the correct initial setup to determine the decay rate ?
A public health technician is monitoring a sanitization process where a bacteria population declines from 700,000 to 400,000 units in 5 hours. To predict the population remaining after 24 hours using the model , arrange the following steps in the correct order.
A laboratory technician is evaluating the decline of a bacterial culture using the exponential decay model . After substituting the initial and final population values into the formula, the technician must apply the ____ logarithm to both sides of the equation to solve for the decay rate .
A laboratory technician is monitoring a bacterial culture that declines from 700,000 to 400,000 units over a period of 5 hours. To model this decline using the exponential decay formula , True or False: The value 700,000 should be substituted for the variable (initial amount) and the value 400,000 should be substituted for the variable (final amount).
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