SOLUTION: The number of punishing websites (fraudulent websites designed to trick victims into revealing personal financial information) is growing by 15% each month. In June 2005, there wer

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Question 1058298: The number of punishing websites (fraudulent websites designed to trick victims into revealing personal financial information) is growing by 15% each month. In June 2005, there were 4000 phishing website.
a) Write a formula for the number of phishing websites as a function of months since June 2005.

b) How long will it take for the number of sites to reach 8000? Give both an exact value and a decimal approximation rounded to two decimal places.

c) How long should it take for the number of sites to reach 16,000?

Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
The number of punishing websites (fraudulent websites designed to trick victims into revealing personal financial information) is growing by 15% each month. In June 2005, there were 4000 phishing website.
a) Write a formula for the number of phishing websites as a function of months since June 2005.
n = 4000*1.15^t (t in months)
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b) How long will it take for the number of sites to reach 8000? Give both an exact value and a decimal approximation rounded to two decimal places.
8000 = 4000*1.15^t
1.15^t = 2
t*log(1.15) = log(2)
t = log(2)/log(1.15) months
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t =~ 4.96 months
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c) How long should it take for the number of sites to reach 16,000?
Same method as b.