document.write( "Question 436823: How long does it take $875 to double if it is invested at 8% compounded monthly? \n" ); document.write( "

Algebra.Com's Answer #853288 by MathTherapy(10587) $\"\"$ $\"About$

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document.write( "How long does it take $875 to double if it is invested at 8% compounded monthly?\r\n" );
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document.write( "Future value of $1 formula: \r\n" );
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document.write( "Doesn't matter what P is, A will ALWAYS be 2 (DOUBLE). \r\n" );
document.write( "So, substituting 2 for A (Accumulated amount/Future Value), 1 for P (Principal, or Initial Investment/Amount), .08 for\r\n" );
document.write( "i (interest rate, as a percent/decimal), 12 for m (number of annual coumpounding periods), t (time, in years) is UNKNOWN.\r\n" );
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document.write( "With that,  now becomes: \r\n" );
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document.write( "          ----- Converting to LOGARITHMIC form\r\n" );
document.write( "  Time, or , or approximately 8.693189 years, or 8 years, 8.3183 months, or 104.3183 months. \r\n" );
document.write( "This amount is then ROUNDED to a time of 105 months, or 8 years, and 9 months.\r\n" );
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document.write( "As stated by Tutor @IKLEYN, the 8.3183 years, or 104.3813 months MUST be ROUNDED UP to the next INTEGER, which is 105.\r\n" );
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document.write( "Note that at the 104th-month, or 8-year, 8-month juncture, the amount will NOT have doubled. One has to wait until the 105th\r\n" );
document.write( "month to see the invested amount DOUBLE.

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