document.write( "Question 588088: Struggling with this compound interest question. Please help if you can and provide a detailed explanation of how you got the answer.\r
\n" ); document.write( "\n" ); document.write( "Joe invested $6000 on Feb 22nd, 2012 into an account earning 3 ¾%
\n" ); document.write( "compounded monthly. How many days will it take for his investment to earn
\n" ); document.write( "$2000 in interest?
\n" ); document.write( "
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Algebra.Com's Answer #374368 by lwsshak3(11628)\"\" \"About 
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Joe invested $6000 on Feb 22nd, 2012 into an account earning 3 ¾%
\n" ); document.write( "compounded monthly. How many days will it take for his investment to earn
\n" ); document.write( "$2000 in interest?
\n" ); document.write( "**
\n" ); document.write( "Compound Interest Formula: A=P(1+r)^n, P=initial investment, r=interest rate per period, n=number of periods, A=amount after n periods.
\n" ); document.write( "For given problem:
\n" ); document.write( "P=6000
\n" ); document.write( "r=.0375/12=.003125
\n" ); document.write( "n=what we are to find (how many monthsI
\n" ); document.write( "A=amount after n-periods=initial investment +interest=6000+2000=8000
\n" ); document.write( "..
\n" ); document.write( "8000=6000(1+.003125)^n
\n" ); document.write( "8000=6000(1.003125)^n
\n" ); document.write( "8000/6000=(1.003125)^n
\n" ); document.write( "4/3=(1.003125)^n
\n" ); document.write( "take log of both sides:
\n" ); document.write( "log(4/3)=nlog(1.003125)
\n" ); document.write( "n=log(4/3)/log(1.003125)
\n" ); document.write( "using calculator
\n" ); document.write( "n=≈92 months≈2766 days (assumed 30 days/mo)
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