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TEST YOUR UNDERSTANDING
Suppose we start with
EXAMPLE 1.9 PURIFYING WATER
Water that is initially contaminated with a concentration of 9 milligrams of pollutant per liter of water is subjected to a cleaning process. The cleaning process is able to reduce the pollutant concentration by 25% each hour. Let
Part 1 What is the concentration of pollutant in the water after 3 hours?
Part2 Compare the results predicted by the verbal description at the end of each of the first 3 hours with those given by the formula
Part 3 The formula given in part 2 is, in fact, the correct one. Use it to find the concentration of pollutant after
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Chapter 1 Solutions
Functions and Change: A Modeling Approach to College Algebra (MindTap Course List)
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College Algebra Essentials
College Algebra (6th Edition)
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