document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=119880>Question 119880</A>: <I><SPAN STYLE=\"word-break: break-all;\"> I've been trying to work this problem, but I'm stumped.  I have been trying it with the variable rate equations A=RB and variable rate + fixed rate = total rate.  Here is the problem:  A 60watt bulb cost 50 cents to buy and 12 cents per day to use (24hrs).  Another bulb cost $2.50 to buy and 2 cents per day to use.  How many days of use will it take for the cost of the bulbs to be equal and what is the equivalent cost? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #87849 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=87849\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> A 60watt bulb cost 50 cents to buy and 12 cents per day to use (24hrs). Another bulb cost $2.50 to buy and 2 cents per day to use. How many days of use will it take for the cost of the bulbs to be equal and what is the equivalent cost?<BR>\n" );
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document.write( "1st Bulb Cost for x days of use: A(x) = 0.50+0.12x<BR>\n" );
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document.write( "2nd Bulb Cost for x days of use: B(x) = 2.50 + 0.02x<BR>\n" );
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document.write( "EQUATION:<BR>\n" );
document.write( "When does A(x) = B(x) ?<BR>\n" );
document.write( "0.50+0.12x = 2.50 + 0.02x<BR>\n" );
document.write( "2.00 = 0.10x<BR>\n" );
document.write( "x = 20 days<BR>\n" );
document.write( "A and B have equivalent costs for 20 days of use.<BR>\n" );
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document.write( "The cost when x=20 days:<BR>\n" );
document.write( "A(20) = 0.50 + 0.12*20 = 0.50+2.40 = 2.90<BR>\n" );
document.write( "B(20) = 2.50 + 0.02*20 = 2.50+40 = 2.90<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H.<BR>\n" );
document.write( " </SPAN>\n" );
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