document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=377863>Question 377863</A>: <I><SPAN STYLE=\"word-break: break-all;\"> In 1920 a record for a race was 45.3 seconds. In 1940 it was 44.7 seconds.\r<BR>\n" );
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document.write( "R(t)= the Records of the race and let t = the number of years since 1920.\r<BR>\n" );
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document.write( "1.Find a linear function that fits the Data<BR>\n" );
document.write( "2. Use the function to predict the race 2003, and 2006<BR>\n" );
document.write( "3. Find the year when the record will be 42.5 seconds.\r<BR>\n" );
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document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #268486 by </B><A HREF=/tutors/aboutme.mpl?userid=mananth><B>mananth(16946)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=mananth><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=mananth><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=268486\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> In 1920 a record for a race was 45.3 seconds.<BR>\n" );
document.write( "In 1940 it was 44.7 seconds.<BR>\n" );
document.write( "decrease per year = (45.3-44.7) /20<BR>\n" );
document.write( "=0.6/20<BR>\n" );
document.write( "=0.03 per year.<BR>\n" );
document.write( "R(t) = 45.3-0.03t<BR>\n" );
document.write( "......<BR>\n" );
document.write( "In 2003<BR>\n" );
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document.write( "R(83)= 45.5-0.03*83<BR>\n" );
document.write( "R(83)=45.5 -2.49<BR>\n" );
document.write( "R(83)=42.81<BR>\n" );
document.write( "In 2003 the record will be 42.81 seconds.<BR>\n" );
document.write( "plug t=86 for 2006<BR>\n" );
document.write( "..<BR>\n" );
document.write( "3.) 42.5 = 45.5 -0.03t<BR>\n" );
document.write( "0.03t=45.5-42.5<BR>\n" );
document.write( "0.03 t = 3<BR>\n" );
document.write( "t = 3/0.03<BR>\n" );
document.write( "t=100 <BR>\n" );
document.write( "Add 100 years to 1920= 2020<BR>\n" );
document.write( "In 2020 the recoed will be 42.5 seconds<BR>\n" );
document.write( "m.ananth@hotmail.ca\r<BR>\n" );
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