document.write( "Question 270747: please help me with this problem..
\n" ); document.write( "in 2005 consumers received an average of 3253 spam messages.the volume of spam messages is decreasing with an exponential decay rate of 13.7% per year.
\n" ); document.write( "a--find th eexponential decay function that can be used to predict average number of spam messages m(t)+years after 2005.
\n" ); document.write( "b--predict the number of spam messagesreceived per consumer in 2010.
\n" ); document.write( "c--in what year will the average consumer receive 100 spam messages?
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Algebra.Com's Answer #198282 by stanbon(75887)\"\" \"About 
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please help me with this problem..
\n" ); document.write( "in 2005 consumers received an average of 3253 spam messages.the volume of spam messages is decreasing with an exponential decay rate of 13.7% per year.
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\n" ); document.write( "If the decay rate is 13.7%, the survival rate is 86.3%
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\n" ); document.write( "a--find th exponential decay function that can be used to predict average number of spam messages m(t)+years after 2005.
\n" ); document.write( "A(t) = 3253(0.863)^t where t is the number of years after 2005
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\n" ); document.write( "b--predict the number of spam messages received per consumer in 2010.
\n" ); document.write( "A(5) = 3253(0.863)^5 = 1557.18
\n" ); document.write( "Rounding up get A(5) is approximately 1558
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\n" ); document.write( "c--in what year will the average consumer receive 100 spam messages?
\n" ); document.write( "Solve for \"t\":
\n" ); document.write( "100 = 3253(0.863)^t
\n" ); document.write( "0.863^t = 0.06418
\n" ); document.write( "t = log(0.06418)/log(0.863) = 18.64 yrs
\n" ); document.write( "Round up: t = 19 yrs.
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\n" ); document.write( "Cheers,
\n" ); document.write( "Stan H.
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