Concept explainers
Reminder Round all answers to two decimal places unless otherwise indicated.
An Inappropriate Linear Model for Radioactive Decay This is a continuation of Exercise 14. Physicists have established that radioactive substances display constant percentage decay, and thus radioactive decay is appropriately modeled exponentially. This exercise is designed to show how using data without an understanding of the phenomenon that generated them can lead to inaccurate conclusions.
a. Plot the data points from Exercise 14. Do they appear almost to fall on a straight line?
b. Find the equation of the regression line and add its graph to the one you made in part a.
c. If you used the regression line as a model for decay of
d. The linear model represented by the regression line makes an absurd prediction ‘concerning the amount of uranium Uranium-239 remaining after 1 hour. What is this prediction?
14. The half life of
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a. Show that these are exponential data and find an exponential model (For this problem, round all your answers to three decimal places.)
b. What is the percentage decay rate each minute? What does this number mean in practical terms?
c. Use functional notation to express the amount remaining after 10 minutes and then calculate the value.
d. What is the half life of
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Functions and Change: A Modeling Approach to College Algebra (MindTap Course List)
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