document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1195403>Question 1195403</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Dominique is purchasing a car priced at $20,000. At the time of purchase, he will also buy additional equipment for the car, which is priced at d dollars. There is a 5 percent sales tax on Dominique’s total purchase. If he pays $25,200, including tax, for the car and the additional equipment, what is the value of d?  <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 #827884 by </B><A HREF=/tutors/aboutme.mpl?userid=math_tutor2020><B>math_tutor2020(3817)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=math_tutor2020><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=827884\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <font color=black size=3><BR>\n" );
document.write( "The car is $20,000 before tax and any add-ons. <BR>\n" );
document.write( "Dominique pays an additional d dollars, where d is some positive real number, for extra equipment.\r<BR>\n" );
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document.write( "The pre-tax subtotal is 20,000+d\r<BR>\n" );
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document.write( "The after-tax amount is 5% larger, so we multiply by 1.05<BR>\n" );
document.write( "Think of it like saying 100% + 5% = 1 + 0.05 = 1.05\r<BR>\n" );
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document.write( "So 1.05*(20,000+d) represents the final amount paid when tax is included.<BR>\n" );
document.write( "This amount is stated as $25,200\r<BR>\n" );
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document.write( "Let's solve for d.<BR>\n" );
document.write( "There are at least two ways to do so.\r<BR>\n" );
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document.write( "Method 1<BR>\n" );
document.write( "1.05*(20,000+d) = 25,200<BR>\n" );
document.write( "20,000+d = (25,200)/(1.05)<BR>\n" );
document.write( "20,000+d = 24,000<BR>\n" );
document.write( "d = 24,000-20,000<BR>\n" );
document.write( "d = 4,000\r<BR>\n" );
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document.write( "Method 2<BR>\n" );
document.write( "1.05*(20,000+d) = 25,200<BR>\n" );
document.write( "1.05*20,000+1.05*d = 25,200<BR>\n" );
document.write( "21,000+1.05*d = 25,200<BR>\n" );
document.write( "1.05*d = 25,200-21,000<BR>\n" );
document.write( "1.05*d = 4,200<BR>\n" );
document.write( "d = (4,200)/(1.05)<BR>\n" );
document.write( "d = 4,000\r<BR>\n" );
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document.write( "Feel free to pick your favorite method, or use some other method entirely. \r<BR>\n" );
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document.write( "In method 1, I divided both sides by 1.05 and subtracted 20,000 from both sides.<BR>\n" );
document.write( "In method 2, I distributed first. Then subtracted 21,000 from both sides. The last step was dividing both sides by 1.05\r<BR>\n" );
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document.write( "Answer: <font color=red>$4,000</font><BR>\n" );
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