document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=390844>Question 390844</A>: <I><SPAN STYLE=\"word-break: break-all;\"> I am trying to help my daughter understand how to solve a word problem but can't remember how to solve it myself - <BR>\n" );
document.write( "\"If sales of 30 cattle bring in a profit of $4500 and  sales of 50 cattle bring in a profit of $12,500, and the profit model is linear, how much profit will the sale of 75 cattle bring in?\"<BR>\n" );
document.write( "$4,500 divided by 30 = $150 per head<BR>\n" );
document.write( "$12,500 divided by 50 = $250 per head<BR>\n" );
document.write( "my thought was that linear would mean 75 x $350 = $26,250 but that was not one of the multiple choice answers </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #277191 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=277191\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> If sales of 30 cattle bring in a profit of $4500 and sales of 50 cattle bring in a profit of $12,500, and the profit model is linear, how much profit will the sale of 75 cattle bring in?<BR>\n" );
document.write( "---<BR>\n" );
document.write( "You have two points relating # of cattle and profit:<BR>\n" );
document.write( "(30,4500) and (50,12500)<BR>\n" );
document.write( "---<BR>\n" );
document.write( "The linear equation has the form p = mc + b<BR>\n" );
document.write( "where p is profit and c is number of cattle.<BR>\n" );
document.write( "-------------------<BR>\n" );
document.write( "m is the slope of the equation:<BR>\n" );
document.write( "m = (12500-4500)/(50-30) = 8000/20 = 400<BR>\n" );
document.write( "-----<BR>\n" );
document.write( "Find \"b\" using p=4500 when c=30 and m = 400:<BR>\n" );
document.write( "4500 = 400*30 + b<BR>\n" );
document.write( "b = 4500-12000<BR>\n" );
document.write( "b = -7500<BR>\n" );
document.write( "----<BR>\n" );
document.write( "Equation:<BR>\n" );
document.write( "p(c) = 400c - 7500<BR>\n" );
document.write( "----<BR>\n" );
document.write( "Solve: \"how much profit will the sale of 75 cattle bring in?\"<BR>\n" );
document.write( "p(75) = 400*75 - 7500<BR>\n" );
document.write( "p(75) = $22,500<BR>\n" );
document.write( "==================<BR>\n" );
document.write( "Cheers,<BR>\n" );
document.write( "Stan H.<BR>\n" );
document.write( " </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );