document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=564187>Question 564187</A>: <I><SPAN STYLE=\"word-break: break-all;\"> I have attempted most of this myself however; I feel like I might have gotten a bit confused when it came to solving for 10,100,1000. This is due today! Thank you for your help!!!\r<BR>\n" );
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document.write( "	An electric company charges $7.50 per month plus $0.09 for each kilowatt hour (kwh) of electricity used.   \r<BR>\n" );
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document.write( "	Use C as the total cost and n as the number of kwh.  Write an expression that gives the total cost of n kwh of electricity.<BR>\n" );
document.write( "C=7.50+0.09n\r<BR>\n" );
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document.write( "	You can find the average cost per kwh by dividing total cost by number of kwh. Write the expression that gives the average cost per kwh.<BR>\n" );
document.write( "C(kwh)=C/n<BR>\n" );
document.write( "	Find the average cost per kwh for 10 kwh, 100 kwh, and 1,000 kwh.<BR>\n" );
document.write( "10 kwh You would first start by finding the overall cost <BR>\n" );
document.write( "C=7.50+0.09(10)<BR>\n" );
document.write( "C=7.50+0.90<BR>\n" );
document.write( "C=0.84 kwh<BR>\n" );
document.write( "Next plug in 0.84 for C and 10 for n.<BR>\n" );
document.write( "C(kwh)=0.84/10<BR>\n" );
document.write( "C(kwh)=0.084\r<BR>\n" );
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document.write( "100 kwh<BR>\n" );
document.write( "C=7.50+0.09(100)<BR>\n" );
document.write( "C=7.50+9<BR>\n" );
document.write( "C=16.50\r<BR>\n" );
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document.write( "C(kwh)=16.50/100<BR>\n" );
document.write( "C(kwh)=0.165\r<BR>\n" );
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document.write( "1000 kwh<BR>\n" );
document.write( "C=7.50+0.09(1000)<BR>\n" );
document.write( "C=7.50+90<BR>\n" );
document.write( "C=97.50\r<BR>\n" );
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document.write( "C(kwh)=97.50/1000<BR>\n" );
document.write( "C(kwh)=0.0975\r<BR>\n" );
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document.write( "	As the number of kwh increases, what happens to the average cost of the kwh? Would the average cost ever fall below $0.09? If so, identify a value that supports your answer. If not, explain how you know. <BR>\n" );
document.write( "As the number of kwh increases the average cost of the kwh decreases. <BR>\n" );
document.write( "	How many kwh should be purchased for the average cost to be $0.12 per kwh? <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 #365326 by </B><A HREF=/tutors/aboutme.mpl?userid=KMST><B>KMST(5328)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=KMST><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=KMST><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=365326\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> You were asked<BR>\n" );
document.write( "Write an expression that gives the total cost of n kwh of electricity.<BR>\n" );
document.write( "C=7.50+0.09n is a good answer<BR>\n" );
document.write( "You were also asked<BR>\n" );
document.write( "Write the expression that gives the average cost per kwh.<BR>\n" );
document.write( "C(kwh)=C/n is OK, but it has two problems.<BR>\n" );
document.write( "An equivalent expression was expected, and using the same letter C for the total cost and the cost per kwh is confusing.<BR>\n" );
document.write( "I will use K for the average cost per kwh, and<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=K=C%2Fn=%287.50%2B0.09n%29%2Fn=7.5%2Fn%2B0.09 ALIGN=MIDDLE  ALT=\"K=C%2Fn=%287.50%2B0.09n%29%2Fn=7.5%2Fn%2B0.09\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=K=7.5%2Fn%2B0.09 ALIGN=MIDDLE  ALT=\"K=7.5%2Fn%2B0.09\"   DISABLED_style= \"max-width:90%; height:auto;\" > was the expression expected because it gives you a single expression as a function of n (no intermediate calculations).<BR>\n" );
document.write( "That is expected in algebra and calculus.<BR>\n" );
document.write( "I also know that was the intended answer, because all the answers to the final questions seem to come directly from there.<BR>\n" );
document.write( "1) As the number of kwh increases, what happens to the average cost of the kwh? You correctly concluded that<BR>\n" );
document.write( "\"As the number of kwh increases the average cost of the kwh decreases.\"<BR>\n" );
document.write( "You could conclude that from the results of the calculations<BR>\n" );
document.write( "2) Would the average cost ever fall below $0.09?<BR>\n" );
document.write( "Looking at <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=K=7.5%2Fn%2B0.09 ALIGN=MIDDLE  ALT=\"K=7.5%2Fn%2B0.09\"   DISABLED_style= \"max-width:90%; height:auto;\" > as a function of n, with n being a positive real number, you see that the answer is NO.<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=K=7.5%2Fn%2B0.09%3E0.09 ALIGN=MIDDLE  ALT=\"K=7.5%2Fn%2B0.09%3E0.09\"   DISABLED_style= \"max-width:90%; height:auto;\" > because <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=7.5%2Fn%3E0 ALIGN=MIDDLE  ALT=\"7.5%2Fn%3E0\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "If so, identify a value that supports your answer. Not aplicable, because it was not so.<BR>\n" );
document.write( "If not, explain how you know.<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=n%3E0 ALIGN=MIDDLE  ALT=\"n%3E0\"   DISABLED_style= \"max-width:90%; height:auto;\" >, so <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=7.5%2Fn%3E0 ALIGN=MIDDLE  ALT=\"7.5%2Fn%3E0\"   DISABLED_style= \"max-width:90%; height:auto;\" >, and  <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=K=7.5%2Fn%2B0.09%3E0.09 ALIGN=MIDDLE  ALT=\"K=7.5%2Fn%2B0.09%3E0.09\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "3) How many kwh should be purchased for the average cost to be $0.12 per kwh?<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=7.5%2Fn%2B0.09=0.12 ALIGN=MIDDLE  ALT=\"7.5%2Fn%2B0.09=0.12\"   DISABLED_style= \"max-width:90%; height:auto;\" > --> <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=7.5%2Fn=0.12-0.09 ALIGN=MIDDLE  ALT=\"7.5%2Fn=0.12-0.09\"   DISABLED_style= \"max-width:90%; height:auto;\" > --> <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=7.5%2Fn=0.03 ALIGN=MIDDLE  ALT=\"7.5%2Fn=0.03\"   DISABLED_style= \"max-width:90%; height:auto;\" > --> <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=7.5=0.03n ALIGN=MIDDLE  ALT=\"7.5=0.03n\"   DISABLED_style= \"max-width:90%; height:auto;\" > --> <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=n=7.5%2F0.03 ALIGN=MIDDLE  ALT=\"n=7.5%2F0.03\"   DISABLED_style= \"max-width:90%; height:auto;\" > --> <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=n=250 ALIGN=MIDDLE  ALT=\"n=250\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
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