document.write( "Question 169194: Someone please help me with the following problem:\r
\n" ); document.write( "\n" ); document.write( "Suppose $5000 is invested at interest rate k, compounded continuously and grows to $6954.84 in 6 years.\r
\n" ); document.write( "\n" ); document.write( "(a) Find the interest rate\r
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\n" ); document.write( "(b) Find the exponential growth function\r
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\n" ); document.write( "\n" ); document.write( "(c) Find the balance after 10 years\r
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\n" ); document.write( "\n" ); document.write( "(d) Find the doubling time\r
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Algebra.Com's Answer #124776 by ankor@dixie-net.com(22740)\"\" \"About 
You can put this solution on YOUR website!
Someone please help me with the following problem:
\n" ); document.write( "Suppose $5000 is invested at interest rate k, compounded continuously and grows to $6954.84 in 6 years.
\n" ); document.write( ":
\n" ); document.write( "The continuous interest formula: \"P%2Ae%5E%28rt%29\" = A
\n" ); document.write( "Where:
\n" ); document.write( "P = initial amt (5000)
\n" ); document.write( "r = interest rate in decimal form (k in this problem)
\n" ); document.write( "t = time, in years (6yrs)
\n" ); document.write( "A = final amt (6954.84)
\n" ); document.write( ":
\n" ); document.write( "(a) Find the interest rate
\n" ); document.write( "\"5000%2Ae%5E%286k%29\" = 6954.84
\n" ); document.write( "\"e%5E%286k%29\" = \"6954.84%2F5000\"
\n" ); document.write( ":
\n" ); document.write( "\"e%5E%286k%29\" = 1.390968; divided both sides by 5000
\n" ); document.write( ":
\n" ); document.write( "6k*ln(e) = ln(1.390968); find the nat log of both sides
\n" ); document.write( ":
\n" ); document.write( "6k = .33; nat log of e is 1
\n" ); document.write( ":
\n" ); document.write( "k = \".33%2F6\"
\n" ); document.write( "k = .055, 5.5% interest
\n" ); document.write( ":
\n" ); document.write( "Check on a calc: enter: 5000*e^(6*.055) = 6954.84
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\n" ); document.write( "(b) Find the exponential growth function
\n" ); document.write( "A = \"5000%2Ae%5E%28.055t%29\"
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\n" ); document.write( ":
\n" ); document.write( "(c) Find the balance after 10 years
\n" ); document.write( "On a calc enter \"5000%2Ae%5E%28%28.055%2A10%29%29\" = 8666.27\r
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\n" ); document.write( "\n" ); document.write( "(d) Find the doubling time
\n" ); document.write( "\"5000%2Ae%5E%28.055t%29\" = 10000; we want to find t here
\n" ); document.write( ":
\n" ); document.write( "\"e%5E%28.055t%29\" = \"10000%2F5000\"
\n" ); document.write( ":
\n" ); document.write( "\"e%5E%28.055%29\" = 2;
\n" ); document.write( ":
\n" ); document.write( ".055t*ln(e) = ln(2); find the nat log of both sides
\n" ); document.write( ":
\n" ); document.write( ".055t = .693;
\n" ); document.write( ":
\n" ); document.write( "t = \".693%2F.055\"
\n" ); document.write( "t = 12.6 yrs
\n" ); document.write( ":
\n" ); document.write( ":
\n" ); document.write( "Check on a calc: enter: 5000*e^(12.6*.055) = 9998.53 ~ 10000
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