document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=877233>Question 877233</A>: <I><SPAN STYLE=\"word-break: break-all;\"> at what rate of simple interest a principal amount becomes three time in 20 years  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #529258 by </B><A HREF=/tutors/aboutme.mpl?userid=fcabanski><B>fcabanski(1391)</B></A><img src=\"/images/stars/stars-12.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=fcabanski><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/images/nopicture.jpg><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=529258\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> i=Prt where i is the interest collected, P is the starting principal, r is the interest rate, and t is the time.  Since the time is given in years, the interest is considered as yearly interest rate.<P><BR>\n" );
document.write( "Call the starting Principal x, since it is unknown.  Add the principal, x, to the accumulated interest, to have three times the original amount.  x is the original amount, 3x is three times the original amount, so 2x interest is needed.<P><BR>\n" );
document.write( "2x = x*20*r<P><BR>\n" );
document.write( "2x=20xr<BR>\n" );
document.write( "2x/20x=r=1/10 = .1 = 10% interest. </SPAN>\n" );
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