SOLUTION: In 2007, 500 millions copies of CDs were sold. The average decrease of sales annually is 1%. What year will annual sales reach 1 million?

Algebra ->  Exponential-and-logarithmic-functions -> SOLUTION: In 2007, 500 millions copies of CDs were sold. The average decrease of sales annually is 1%. What year will annual sales reach 1 million?      Log On


   

Question 1115961: In 2007, 500 millions copies of CDs were sold. The average decrease of sales annually is 1%. What year will annual sales reach 1 million?
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
In 2007, 500 millions copies of CDs were sold. The average decrease of sales annually is 1%. What year will annual sales reach 1 million?
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Note:: If the decrease is 1%, the surviving rate is 99%.
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Solve:: 500 million*(0.99)^x = 1 million
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0.99^x = 1/500 million
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x = log[1/500]/log[0.99] years
x = 618.35
Ans:: 2007+618.35 = 2625.35 which is in the year 2626
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Cheers,
Stan H.
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