document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=145581>Question 145581</A>: <I><SPAN STYLE=\"word-break: break-all;\"> In 1920, the record for a certain race was 45.9 sec. In 1950, it was 45.0 sec. Let R(t)= the record in the race and t= the number of years since 1920.<BR>\n" );
document.write( "Find a linear function that fits the data.\r<BR>\n" );
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document.write( "R(t)=     <BR>\n" );
document.write( "(round to the nearest hundredth)\r<BR>\n" );
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document.write( "What is the predicted record for 2003?<BR>\n" );
document.write( "(Round to the nearest 10th)\r<BR>\n" );
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document.write( "What is the predicted record for 2006?<BR>\n" );
document.write( "(Round to the nearest 10th)\r<BR>\n" );
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document.write( "Thank you. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #106335 by </B><A HREF=/tutors/aboutme.mpl?userid=stanbon><B>stanbon(75887)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=stanbon><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=106335\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> In 1920, the record for a certain race was 45.9 sec. <BR>\n" );
document.write( "In 1950, it was 45.0 sec. <BR>\n" );
document.write( "Let R(t)= the record in the race and t= the number of years since 1920.\r<BR>\n" );
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document.write( "Find a linear function that fits the data.<BR>\n" );
document.write( "You are given the \"y-intercept\" as (0,45.9)<BR>\n" );
document.write( "Find the slope:<BR>\n" );
document.write( "slope = (45-45.9)/30 = -0.9/30 = -0.03 <BR>\n" );
document.write( "EQUATION:<BR>\n" );
document.write( "R(t)= -0.03t + 45.9<BR>\n" );
document.write( "---------------------------- <BR>\n" );
document.write( "What is the predicted record for 2003?<BR>\n" );
document.write( "t = 83 in 2003<BR>\n" );
document.write( "R(83) = -0.03*83 + 45.9<BR>\n" );
document.write( "R(83) = 43.41<BR>\n" );
document.write( "---------------------<BR>\n" );
document.write( "What is the predicted record for 2006?<BR>\n" );
document.write( "t = 86 in 2006<BR>\n" );
document.write( "R(86) = -0.03*86 + 45.9<BR>\n" );
document.write( "R(86) = 43.32<BR>\n" );
document.write( "====================<BR>\n" );
document.write( "Cheers,<BR>\n" );
document.write( "Stan H.<BR>\n" );
document.write( " </SPAN>\n" );
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