SOLUTION: If the pollution of Lake Erie were stopped suddenly, it has been estimated that the level y of pollutants would decrease according to the formula y = y0e−0.3821t, where t is th

Algebra ->  Logarithm Solvers, Trainers and Word Problems -> SOLUTION: If the pollution of Lake Erie were stopped suddenly, it has been estimated that the level y of pollutants would decrease according to the formula y = y0e−0.3821t, where t is th      Log On


   



Question 1147953: If the pollution of Lake Erie were stopped suddenly, it has been estimated that the level y of pollutants would decrease according to the formula
y = y0e−0.3821t, where t is the time in years and y0 is the pollutant level at which further pollution ceased. How many years would it take to clear 60% of the pollutants? (Round your answer to three decimal places.)

Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
If the pollution of Lake Erie were stopped suddenly, it has been estimated that the level y of pollutants would decrease according to the formula
y = y0e−0.3821t, where t is the time in years and y0 is the pollutant level at which further pollution ceased. How many years would it take to clear 60% of the pollutants?
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60% clear ---> 40% remaining = 0.4
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0.4+=+1%2Ae%5E%28-0.3281t%29
-0.3281t+=+ln%280.4%29
t =~ 2.7927 years