document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=810656>Question 810656</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Kaye has an arrangement with her father where he pays her $5 for every maths test she passes and fines her $10 for every test she fails. Last year Kaye sat 9 tests and altogether her father paid her $15. How many tests did Kaye pass?\r<BR>\n" );
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document.write( "I must work this out with algebra but using a diagram I have worked out that she failed 2 and passed 7. Cna you help me with the algebra please. This is what I have tried so far:\r<BR>\n" );
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document.write( "Let p = pass and f = fail.                     f = -10 so p = f + 15\r<BR>\n" );
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document.write( "5p-10f=15<BR>\n" );
document.write( "5(f+15) -10f=15<BR>\n" );
document.write( "5f +75 -10f = 15<BR>\n" );
document.write( "-5f + 75 = 15<BR>\n" );
document.write( "                     (-75)<BR>\n" );
document.write( "-5f = -60<BR>\n" );
document.write( "                    (divided by -5)<BR>\n" );
document.write( "f = 12\r<BR>\n" );
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document.write( "Please correct any of my working or feel free to start over :) Thanks so much in advance<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 #488335 by </B><A HREF=/tutors/aboutme.mpl?userid=mananth><B>mananth(16946)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=mananth><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=mananth><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=488335\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> p+f=9\r<BR>\n" );
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document.write( "p=9-f\r<BR>\n" );
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document.write( "5p-10f=15\r<BR>\n" );
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document.write( "5(9-f)-10f=15\r<BR>\n" );
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document.write( "45-5f-10f=15\r<BR>\n" );
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document.write( "-15f=-30\r<BR>\n" );
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document.write( "f=2<BR>\n" );
document.write( "p=7\r<BR>\n" );
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document.write( "Check<BR>\n" );
document.write( "7*5 -10*2=15 </SPAN>\n" );
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