document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=54800>Question 54800</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Can someone help me?\r<BR>\n" );
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document.write( "  A principal of $5,000 was invested in a savings account for 4 years.  If the interest earned for the period was $400, what was the interest rate?\r<BR>\n" );
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document.write( " Thank you,<BR>\n" );
document.write( "  Ashley </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #708157 by </B><A HREF=/tutors/aboutme.mpl?userid=greenestamps><B>greenestamps(13200)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=greenestamps><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=greenestamps><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=708157\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <br>You did not state whether interest was simple or compounded.  The first response ignored the fact that the interest was over 4 years; the second response assumed the interest was compound interest.<br><BR>\n" );
document.write( "Because of the numbers, I suspect the intention might have been for the interest to be simple interest.  If that is the case, the numbers work out easily, and we get \"nice\" answers.<br><BR>\n" );
document.write( "For simple interest, the amount of interest is simply the beginning principal, P, multiplied by the interest rate, r, and multiplied by the number of years, t (for \"time\"):<br><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=I+=+Prt ALIGN=MIDDLE  ALT=\"I+=+Prt\"   DISABLED_style= \"max-width:90%; height:auto;\" ><br><BR>\n" );
document.write( "Plugging in the numbers from your problem...<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=400+=+5000%28r%29%284%29 ALIGN=MIDDLE  ALT=\"400+=+5000%28r%29%284%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=400+=+20000r ALIGN=MIDDLE  ALT=\"400+=+20000r\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=r+=+400%2F20000+=+4%2F200+=+2%2F100 ALIGN=MIDDLE  ALT=\"r+=+400%2F20000+=+4%2F200+=+2%2F100\"   DISABLED_style= \"max-width:90%; height:auto;\" ><br><BR>\n" );
document.write( "The interest rate (assuming simple interest) is 2% </SPAN>\n" );
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