document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1207185>Question 1207185</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Mrs. Robinson made the table below showing the yearly balance of her savings<BR>\n" );
document.write( "account. Interest on the account compounds annually. Which of the following<BR>\n" );
document.write( "describes the best model to be used for Mrs. Robinson’s data?<BR>\n" );
document.write( "Year  Balance in Dollars<BR>\n" );
document.write( "0     $400<BR>\n" );
document.write( "5     $463.71<BR>\n" );
document.write( "10    $537.57<BR>\n" );
document.write( "15    $623.19<BR>\n" );
document.write( "20    $722.44<BR>\n" );
document.write( "25    $837.51\r<BR>\n" );
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document.write( "A) a positive linear function<BR>\n" );
document.write( "B) a positive quadratic function<BR>\n" );
document.write( "C) an exponential growth function<BR>\n" );
document.write( "D) a positive absolute value function </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #844919 by </B><A HREF=/tutors/aboutme.mpl?userid=ikleyn><B>ikleyn(52777)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=ikleyn><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=ikleyn><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=844919\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> .<BR>\n" );
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document.write( "Notice that the years in the table are given with the constant step of 5 years.\r\n" );
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document.write( "From your table, calculate the ratio of the next term balance to the previous term balance.\r\n" );
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document.write( "I did it and obtained a constant value of 1.1592 (rounded) for all adjacent terms.\r\n" );
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document.write( "The fact that the consecutive fractions have constant values tells that the function is exponential.\r\n" );
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document.write( "That's all.\r<BR>\n" );
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document.write( "As an additional clue, you may use the fact that banks use <BR>\n" );
document.write( "either linear function (simple percent account) or exponential functions (compounded accounts).<BR>\n" );
document.write( "They never use quadratic functions or absolute value functions as growth functions,<BR>\n" );
document.write( "so for you in this problem the choice is, actually, between linear and exponential, only.\r<BR>\n" );
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document.write( "There is no any need to inflate this bubble to incredible proportions.\r<BR>\n" );
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document.write( " </SPAN>\n" );
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