document.write( "Question 954649: Sarah invested 100 dollars in a bank account with an interest rate of 2% compounded quarterly. After approximately how many years will it take for her money to double? \n" ); document.write( "
Algebra.Com's Answer #583092 by josgarithmetic(39628)\"\" \"About 
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2%, same as 0.02, if compounded quarterly means each period of compounding the rate is \"0.02%281%2F4%29=0.005\"\r
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\n" ); document.write( "\n" ); document.write( "\"200=100%2A%281.005%29%5Ep\", using p to count the periods.\r
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\n" ); document.write( "\n" ); document.write( "One way to solve is to find p, and then find \"p%2F4\" to find how many years.
\n" ); document.write( "Other way is p/4=y for years, \"p=4%2Ay\" and do the equation as
\n" ); document.write( "\"200=100%2A%281.05%29%5E%284y%29\".\r
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\n" ); document.write( "\n" ); document.write( "\"%281.005%29%5Ep=2\"
\n" ); document.write( "\"log%2810%2C1.005%29%2Ap=log%2810%2C2%29\"
\n" ); document.write( "\"p=log%2810%2C2%29%2Flog%2810%2C1.005%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"p=140\"----quarters
\n" ); document.write( "\"y=140%2F4=highlight%2834%263%2F4%29\"----years\r
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