document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=979993>Question 979993</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A Grade 8 class is planning to have a field trip. The survey showed that if the contribution is $200., 12 students will join and if the contribution will be reduced to $160, 20 students will join. How can you predict the number of participants for any given contribution (x)? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #601297 by </B><A HREF=/tutors/aboutme.mpl?userid=josgarithmetic><B>josgarithmetic(39630)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=josgarithmetic><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=601297\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> The description gives two data points.<BR>\n" );
document.write( "Using x for the contribution quantity and y for the number of students that join, the points are  (200,12)  and  (160,20).  Your decision of what kind of relationship fit do you use.  You might want a linear fit.\r<BR>\n" );
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document.write( "slope, <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=m=%2820-12%29%2F%28160-200%29=8%2F%28-40%29=-1%2F5 ALIGN=MIDDLE  ALT=\"m=%2820-12%29%2F%28160-200%29=8%2F%28-40%29=-1%2F5\"   DISABLED_style= \"max-width:90%; height:auto;\" >.\r<BR>\n" );
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document.write( "vertical intercept, b=y-mx, choose either point,<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=b=12%2B%281%2F5%29200=12%2B40=32 ALIGN=MIDDLE  ALT=\"b=12%2B%281%2F5%29200=12%2B40=32\"   DISABLED_style= \"max-width:90%; height:auto;\" >.\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=highlight%28y=-x%2F5%2B32%29 ALIGN=MIDDLE  ALT=\"highlight%28y=-x%2F5%2B32%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > </SPAN>\n" );
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