document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=934476>Question 934476</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Thank you very much for taking the time to help me!\r<BR>\n" );
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document.write( "My question relates to fractional algebra.\r<BR>\n" );
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document.write( "Question:\r<BR>\n" );
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document.write( "Sydney’s present age is one-half of Marcus’s present age. In 12 years, Sydney’s age will be five-eighths of Marcus’s age. Find their present ages\r<BR>\n" );
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document.write( "My Attempt:\r<BR>\n" );
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document.write( "Let:\r<BR>\n" );
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document.write( "s = Sydney's age<BR>\n" );
document.write( "m = Marcus's age\r<BR>\n" );
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document.write( "Therefore:\r<BR>\n" );
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document.write( "Sydney's current age = 1/2m\r<BR>\n" );
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document.write( "In 12 years time:\r<BR>\n" );
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document.write( "s = 5/8(m + 12)\r<BR>\n" );
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document.write( "m = m + 12\r<BR>\n" );
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document.write( "The equation I set up is:\r<BR>\n" );
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document.write( "5/8(m+12) = m + 12<BR>\n" );
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document.write( "8 [5/8(m + 12)] = 8 (m + 12)\r<BR>\n" );
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document.write( "5(m + 12) = 8m + 96\r<BR>\n" );
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document.write( "5m + 60 = 8m + 96\r<BR>\n" );
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document.write( "5m - 8m + 60 = 8m - 8m +96\r<BR>\n" );
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document.write( "-3m + 60 = 96\r<BR>\n" );
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document.write( "-3m + 60 - 60 = 96 - 60\r<BR>\n" );
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document.write( "-3m = 36<BR>\n" );
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document.write( "-3m/3 = 36/3\r<BR>\n" );
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document.write( "-m = 12\r<BR>\n" );
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document.write( "m = -12\r<BR>\n" );
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document.write( "Obviously this is the wrong answer as an age cannot be negative. Also, the textbook provided me with the answer of 18 for Sydney and 36 for Marcus.\r<BR>\n" );
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document.write( "Thank you very much for all your help.\r<BR>\n" );
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document.write( "Kind regards,\r<BR>\n" );
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document.write( "Mark Beaton<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 #567468 by </B><A HREF=/tutors/aboutme.mpl?userid=rothauserc><B>rothauserc(4718)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=rothauserc><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=rothauserc><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=567468\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> let m be Marcus's age, s be Sydney's age then we have<BR>\n" );
document.write( "s = m/2<BR>\n" );
document.write( "s+12 = 5/8*(m +12)<BR>\n" );
document.write( "substitute for s in second equation<BR>\n" );
document.write( "m/2 +12 = 5/8*(m +12)<BR>\n" );
document.write( "m/2 + 12 = 5m/8 + 5/8*12<BR>\n" );
document.write( "multiply both sides of = by 8<BR>\n" );
document.write( "4m +96 = 5m + 60<BR>\n" );
document.write( "m = 36<BR>\n" );
document.write( "s = 18\r<BR>\n" );
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