document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=620790>Question 620790</A>: <I><SPAN STYLE=\"word-break: break-all;\"> The sum of the ages of the two students is 36. Four years from now the ratio of their will be 4:7. Find their present ages? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #390513 by </B><A HREF=/tutors/aboutme.mpl?userid=ankor@dixie-net.com><B>ankor@dixie-net.com(22740)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=ankor@dixie-net.com><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=ankor@dixie-net.com><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=390513\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Two students, a & b, ages now<BR>\n" );
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document.write( "Write an equation for each statement:<BR>\n" );
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document.write( "The sum of the ages of the two students is 36.<BR>\n" );
document.write( "a + b = 36<BR>\n" );
document.write( "b = (36-a); use this for substitution<BR>\n" );
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document.write( "Four years from now the ratio of their will be 4:7.<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%28a%2B4%29%2F%28b%2B4%29 ALIGN=MIDDLE  ALT=\"%28a%2B4%29%2F%28b%2B4%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=4%2F7 ALIGN=MIDDLE  ALT=\"4%2F7\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "CRoss multiply<BR>\n" );
document.write( "7(a+4) = 4(b+4)<BR>\n" );
document.write( "7a + 28 = 4b + 16<BR>\n" );
document.write( "7a = 4b + 16 - 28<BR>\n" );
document.write( "7a = 4b - 12<BR>\n" );
document.write( "Replace b with (36-a)<BR>\n" );
document.write( "7a = 4(36-a) - 12<BR>\n" );
document.write( "7a = 144 - 4a - 12<BR>\n" );
document.write( "7a + 4a = 144 - 12<BR>\n" );
document.write( "11a = 132<BR>\n" );
document.write( "a = 132/11<BR>\n" );
document.write( "a = 12 yrs now<BR>\n" );
document.write( "then<BR>\n" );
document.write( "b = 36 - 12<BR>\n" );
document.write( "b = 24 yrs now<BR>\n" );
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document.write( "Check this; add 4 yrs to their ages, and see what the ratio is.<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=16%2F28 ALIGN=MIDDLE  ALT=\"16%2F28\"   DISABLED_style= \"max-width:90%; height:auto;\" > = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=4%2F7 ALIGN=MIDDLE  ALT=\"4%2F7\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "  </SPAN>\n" );
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