document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1186448>Question 1186448</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Find the amount owed on an investment of P 10,000 into a money market account that pays a simple interest rate of 1.75% over a 39-week period. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #817765 by </B><A HREF=/tutors/aboutme.mpl?userid=Theo><B>Theo(13342)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Theo><IMG SRC=http://www.algebra.com/images/aboutme-small.gif BORDER=0 alt=\"About Me\" VALIGN=MIDDLE></A>&nbsp;<IMG SRC=http://www.algebra.com/cgi-bin/show-face.mpl?user=Theo><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=817765\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> simple interest formula is:\r<BR>\n" );
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document.write( "i = p * r * t\r<BR>\n" );
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document.write( "f = p + i\r<BR>\n" );
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document.write( "replace i with p * r * t and you get:\r<BR>\n" );
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document.write( "f = p + p * r * t\r<BR>\n" );
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document.write( "if you factor out the p, you get:\r<BR>\n" );
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document.write( "f = p * (1 + r * t)\r<BR>\n" );
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document.write( "p is the principal<BR>\n" );
document.write( "r is the interest rate per time period<BR>\n" );
document.write( "t is the number of time periods<BR>\n" );
document.write( "f is the future value\r<BR>\n" );
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document.write( "in this problem:\r<BR>\n" );
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document.write( "p =  10,000<BR>\n" );
document.write( "r = 1.75% per year.<BR>\n" );
document.write( "n = 39 weeks.\r<BR>\n" );
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document.write( "since one year is equal to 52 weeks, you can convert the number of weeks into years by dividing 39 by 52 to get .75 years.\r<BR>\n" );
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document.write( "since you want to know what is owed at the end of the time investment period, your formula would be:\r<BR>\n" );
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document.write( "f = p + p * r * t, which can also be shown as:<BR>\n" );
document.write( "f = p * (1 + r * t).\r<BR>\n" );
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document.write( "when r is in years and t is in years, the formula becomes:<BR>\n" );
document.write( "f = 10,000 * ( 1 + .0175 * .75) = 10,131.25\r<BR>\n" );
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document.write( "that's what is owed at the end of the 39 week period.\r<BR>\n" );
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document.write( "you can also work the problem in weeks.<BR>\n" );
document.write( "to do that, you need the interest rate per week.<BR>\n" );
document.write( "the interest rate per week is equal to .0175 per year divided by 52.<BR>\n" );
document.write( "the formula becomes:<BR>\n" );
document.write( "f = 10,000 * (1 + .0175/52 * 39) = 10,131.25\r<BR>\n" );
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document.write( "alternatively, you can just solve for the interest first and then add it to the principal.\r<BR>\n" );
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document.write( "the formula for interest is i = p * r * t.<BR>\n" );
document.write( "this becomes:<BR>\n" );
document.write( "i = 10,000 * .0175 * 39/52 = 131.25<BR>\n" );
document.write( "add that to 10,000 to get 10,131.25.\r<BR>\n" );
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document.write( "in all of these formulas, the interest rate is used, not the percent.<BR>\n" );
document.write( "rate = percent / 100.<BR>\n" );
document.write( "1.75% is therefore equal to a rate of .0175.\r<BR>\n" );
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document.write( "the time periods must be consistent.<BR>\n" );
document.write( "if the rate is per year, the number of time periods has to be in years.<BR>\n" );
document.write( "if the number of time periods is in weeks, the rate must be per week.\r<BR>\n" );
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document.write( " </SPAN>\n" );
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