document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=985541>Question 985541</A>: <I><SPAN STYLE=\"word-break: break-all;\"> I need to find a formula to answer an investment increase word problem. I know the interest rate compounded annually and the total amount received. I need to find the original investment amount.  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #606400 by </B><A HREF=/tutors/aboutme.mpl?userid=macston><B>macston(5194)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=macston><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=macston><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=606400\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> P=principal (original investment); r=interest rate (expressed as decimal); t=time(must match rate time- if rate is 5% per year, time must be in years); I=amount of interest.<BR>\n" );
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document.write( "I=Prt Can be solved for any of the variables.<BR>\n" );
document.write( "P=I/rt Divide each side by rt.<BR>\n" );
document.write( "r=I/Pt Divide each side by Pt.<BR>\n" );
document.write( "t=I/Pr Divide each side by Pr.<BR>\n" );
document.write( ". <BR>\n" );
document.write( "To find original investment, P, you must know (or be able to calculate) Interest received (I), interest rate (r), and time invested (t). </SPAN>\n" );
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