document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=499020>Question 499020</A>: <I><SPAN STYLE=\"word-break: break-all;\"> By increasing her usual speed by 25 kilometers per hour, a bus driver decreases the time on a 25-kilometer trip by 10 minutes. Find the usual speed.\r<BR>\n" );
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document.write( " The Vilas County News earns a profit of $20 per year for each of its 3,000 subscribers. Management projects that the profit per subscriber would increase by 1¢ for each additional subscriber over the current 3,000. How many total subscribers are needed to bring a total profit of $113,100?<BR>\n" );
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document.write( "Perform the operations and simplify. 1/x times x^2-15x all over x-14 </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #337350 by </B><A HREF=/tutors/aboutme.mpl?userid=ankor@dixie-net.com><B>ankor@dixie-net.com(22740)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=ankor@dixie-net.com><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=ankor@dixie-net.com><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=337350\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> By increasing his usual speed by 25 kilometers per hour, a bus driver decreases the time on a 25-kilometer trip by 10 minutes.<BR>\n" );
document.write( " Find the usual speed.<BR>\n" );
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document.write( "Let s = his usual speed<BR>\n" );
document.write( "Change 10 min to 1/6 hr<BR>\n" );
document.write( "write a time equation; time = dist/speed<BR>\n" );
document.write( "Usual time - 10 min = faster time<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=25%2Fs ALIGN=MIDDLE  ALT=\"25%2Fs\"   DISABLED_style= \"max-width:90%; height:auto;\" > - <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=1%2F6 ALIGN=MIDDLE  ALT=\"1%2F6\"   DISABLED_style= \"max-width:90%; height:auto;\" > = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=25%2F%28%28s%2B25%29%29 ALIGN=MIDDLE  ALT=\"25%2F%28%28s%2B25%29%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "multiply by 6s(s+25), results<BR>\n" );
document.write( "6(s+25)*25 - s(s+25) = 6s*25<BR>\n" );
document.write( "150(s+25) - s^2 - 25s = 150s<BR>\n" );
document.write( "150s + 3850 - s^2 - 25s = 150s<BR>\n" );
document.write( "Combine as a quadratic equation on the right<BR>\n" );
document.write( "0 = s^2 + 25s - 3750<BR>\n" );
document.write( "Factors to <BR>\n" );
document.write( "(x-50)(x+75) = 0<BR>\n" );
document.write( "Positive solution<BR>\n" );
document.write( "x = 50 mph is his usual speed<BR>\n" );
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document.write( "The Vilas County News earns a profit of $20 per year for each of its 3,000 subscribers.<BR>\n" );
document.write( "Management projects that the profit per subscriber would increase by 1¢ for each additional subscriber over the current 3,000.<BR>\n" );
document.write( " How many total subscribers are needed to bring a total profit of $113,100?<BR>\n" );
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document.write( "Find the present profit: 3000 * $20 = $60000<BR>\n" );
document.write( "then: 113100 - 60000 = $53,100 increase in profits<BR>\n" );
document.write( "Let n = number of subscribers over 3000 to increase profit by 1 cent for each<BR>\n" );
document.write( ".01n = 53100<BR>\n" );
document.write( "n = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=53100%2F.01 ALIGN=MIDDLE  ALT=\"53100%2F.01\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "n = 5,310,000 additional subscribers, doesn't seem very realistic, does it!<BR>\n" );
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document.write( "Perform the operations and simplify. <BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=1%2Fx ALIGN=MIDDLE  ALT=\"1%2Fx\"   DISABLED_style= \"max-width:90%; height:auto;\" > * <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x%5E2-15x ALIGN=MIDDLE  ALT=\"x%5E2-15x\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
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document.write( " (x - 14)<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=1%2Fx ALIGN=MIDDLE  ALT=\"1%2Fx\"   DISABLED_style= \"max-width:90%; height:auto;\" > * <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x%28x-15%29 ALIGN=MIDDLE  ALT=\"x%28x-15%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
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document.write( " (x - 14)<BR>\n" );
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document.write( "Cancel the x and you are left with<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%28x-15%29%2F%28x-14%29 ALIGN=MIDDLE  ALT=\"%28x-15%29%2F%28x-14%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > </SPAN>\n" );
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