document.write( "Question 1137956: Ricky Wow invested $20 000 and the interest was compounded bi-monthly. If this sum
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Algebra.Com's Answer #755815 by ikleyn(52797)\"\" \"About 
You can put this solution on YOUR website!
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document.write( "30000 = \"20000%2A%281%2Br%2F24%29%5E%283.5%2A24%29\"   ====>\r\n" );
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document.write( "\"30000%2F20000\" = \"%281%2Br%2F24%29%5E84\"\r\n" );
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document.write( "\"%281%2Br%2F24%29%5E84\" = \"3%2F2\" = 1.5   ====>\r\n" );
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document.write( "\"84%2Alog%28%281+%2B+r%2F24%29%29\" = log(1.5)\r\n" );
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document.write( "\"log%28%281+%2B+r%2F24%29%29\" = \"log%281.5%29%2F84\" \r\n" );
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document.write( "\"log%28%281+%2B+r%2F24%29%29\" = 0.002096\r\n" );
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document.write( "\"1+%2B+r%2F24%29\" = \"10%5E0.002096\"\r\n" );
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document.write( "\"1+%2B+r%2F24\" = 1.004838  ====>  \"r%2F24\" = 1.004838 - 1 = 0.004838\r\n" );
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document.write( "r = 24*0.004838 = 0.116  (approximately)\r\n" );
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document.write( "ANSWER.  Interest rate is about 0.116 = 11.6% .\r\n" );
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document.write( "CHECK.  \"20000%2A%281%2B0.116%2F24%29%5E84\" = 30011 dollars.\r\n" );
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document.write( "        With the rounding made on the way, the solution and the answer are correct.\r\n" );
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\n" ); document.write( "Tutor @greenestamps made a notice explaining that \"bi-monthly\" means \"one time in two months\".\r
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document.write( "30000 = \"20000%2A%281%2Br%2F6%29%5E%283.5%2A6%29\"   ====>\r\n" );
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document.write( "\"30000%2F20000\" = \"%281%2Br%2F6%29%5E21\"\r\n" );
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document.write( "\"%281%2Br%2F6%29%5E21\" = \"3%2F2\" = 1.5   ====>\r\n" );
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document.write( "\"21%2Alog%28%281+%2B+r%2F6%29%29\" = log(1.5)\r\n" );
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document.write( "\"log%28%281+%2B+r%2F6%29%29\" = \"log%281.5%29%2F21\" \r\n" );
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document.write( "\"log%28%281+%2B+r%2F6%29%29\" = 0.008385\r\n" );
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document.write( "\"1+%2B+r%2F6%29\" = \"10%5E0.008385\" = 1.019495\r\n" );
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document.write( "\"1+%2B+r%2F6\" = 1.019495  ====>  \"r%2F6\" = 1.004838 - 1 = 0.019495\r\n" );
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document.write( "r = 6*0.019495 = 0.117  (approximately)\r\n" );
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document.write( "ANSWER.  Interest rate is about 0.117 = 11.7% .\r\n" );
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document.write( "CHECK.  \"20000%2A%281%2B0.117%2F6%29%5E21\" = 30002.8 dollars.\r\n" );
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document.write( "        With the rounding made on the way, the solution and the answer are correct, \r\n" );
document.write( "        meaning \"bi-monthly\" as \"once per two months\" this time.\r\n" );
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