document.write( "Question 733352: Still trying to help my son with his homework. Here it is.\r
\n" ); document.write( "\n" ); document.write( "Bill needs $4000. If he has $1000, how long should he invest his money in and account compounded continuously at a rate of 9.2%?\r
\n" ); document.write( "\n" ); document.write( "A=4000
\n" ); document.write( "P=1000
\n" ); document.write( "T=?
\n" ); document.write( "r=.092\r
\n" ); document.write( "\n" ); document.write( "4000=1000e^(.092)(t) \r
\n" ); document.write( "\n" ); document.write( "that is a formula that he gave me but I don't know how to get the \"t\" by itself. Help please! Thanks. \n" ); document.write( "
Algebra.Com's Answer #448363 by Edwin McCravy(20062)\"\" \"About 
You can put this solution on YOUR website!
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document.write( "4000 = 1000e(.092)(t)\r\n" );
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document.write( "Divide both sides by 1000\r\n" );
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document.write( "   4 = e(.092t)\r\n" );
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document.write( "Use the definition of a natural logarithm which is:\r\n" );
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document.write( "A = eC is equivalent to the equation C = ln(A)\r\n" );
document.write( "where A = 4 and C = .092t\r\n" );
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document.write( "   ,092t = ln(4)\r\n" );
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document.write( "       t = \"ln%284%29%2F.092\"\r\n" );
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document.write( "       t = 15.06841697 years or about 15 years\r\n" );
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document.write( "Edwin

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