Algebra.Com's Answer #845173 by ikleyn(52802)![\"\"](\"/images/stars/stars-13.gif\")  
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document.write( "How long does $1000 have to be deposited into a savings account at the end of each month
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document.write( "to accumulate to $36,000 if interest is 6.4% compounded monthly?
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document.write( "Use the formula for an Ordinary Annuity saving account compounded monthly \r\n" );
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document.write( " FV =  \r\n" );
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document.write( "where FV is the future value, P is the payment at the end of each month, \r\n" );
document.write( "r is the interest rate per year expressed as decimal, \r\n" );
document.write( "n is the number of monthly deposits (of months).\r\n" );
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document.write( "So, we need to find \" n \" from this equation\r\n" );
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document.write( "  =  =  = 36, \r\n" );
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document.write( "  =  . \r\n" );
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document.write( "Rewrite it in this form\r\n" );
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document.write( " = 0.192,\r\n" );
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document.write( "  = 1 + 0.192 = 1.192.\r\n" );
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document.write( "Take logarithm base 10 of both sides\r\n" );
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document.write( " n*log(1+0.064/12) = log(1.192)\r\n" );
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document.write( "and calculate \r\n" );
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document.write( " n =  = 33.01885 months.\r\n" );
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document.write( "Round it to the closest greater month, which is 34 months. \r\n" );
document.write( "34 months is the same as 2 years and 10 months.\r\n" );
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document.write( "ANSWER. 34 months, or 2 years and 10 months.\r\n" );
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document.write( "Solved.\r
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document.write( "On ordinary annuity saving plan, see my lessons in this site \r
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document.write( " - Ordinary Annuity saving plans and geometric progressions\r
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document.write( " - Solved problems on Ordinary Annuity saving plans \r
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