document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=240593>Question 240593</A>: <I><SPAN STYLE=\"word-break: break-all;\"> My son is completely unclear how to solve this age problem.<BR>\n" );
document.write( "4 years ago Tom was twice as old as John.  4 years from now, John will be 3/4 Tom's age.  How old are they now? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #176258 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=176258\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> 4 years ago Tom was twice as old as John. 4 years from now, John will be 3/4 Tom's age. How old are they now?<BR>\n" );
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document.write( "Let Tom's age NOW be \"t\".<BR>\n" );
document.write( "Let John's age NOW be \"j\".<BR>\n" );
document.write( "--------------------------------<BR>\n" );
document.write( "4 years ago Equation:<BR>\n" );
document.write( "4 years ago Tom was twice as old as John.<BR>\n" );
document.write( "(t-4) = 2(j-4)<BR>\n" );
document.write( "----------------------<BR>\n" );
document.write( "4 years from now Equation:<BR>\n" );
document.write( "John will be (3/4) Tom's age.<BR>\n" );
document.write( "(j+4) = (3/4)(t+4)<BR>\n" );
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document.write( "So use those two equations to solve for \"t\" and for \"j\".<BR>\n" );
document.write( "t-4 = 2j-8<BR>\n" );
document.write( "j+4 = (3/4)t + 3<BR>\n" );
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document.write( "t = 2j-4<BR>\n" );
document.write( "j = (3/4)t - 1<BR>\n" );
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document.write( "Substitute for \"t\" and solve for \"j\":<BR>\n" );
document.write( "j = (3/4)(2j-4)-1<BR>\n" );
document.write( "j = (3/2)j-3-1<BR>\n" );
document.write( "(1/2)j = 4<BR>\n" );
document.write( "j = 8 (John's age NOW)<BR>\n" );
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document.write( "Substitute into t = 2j-4 to solve for \"t\":<BR>\n" );
document.write( "t = 2*8-4 = 12 (Tom's age NOW)<BR>\n" );
document.write( "===============================================<BR>\n" );
document.write( "Cheers,<BR>\n" );
document.write( "Stan H.<BR>\n" );
document.write( " </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );