document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=401587>Question 401587</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Ann's age is seven-tenths of Bill's age. In 4 years Ann's age will be eight-elevenths of Bill's age. How old is Bill now? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #284172 by </B><A HREF=/tutors/aboutme.mpl?userid=josmiceli><B>josmiceli(19441)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=josmiceli><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=josmiceli><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=284172\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Let <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=a ALIGN=MIDDLE  ALT=\"a\"   DISABLED_style= \"max-width:90%; height:auto;\" > = Ann's age now<BR>\n" );
document.write( "Let <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=b ALIGN=MIDDLE  ALT=\"b\"   DISABLED_style= \"max-width:90%; height:auto;\" > = Bill's age now<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=a+%2B+4 ALIGN=MIDDLE  ALT=\"a+%2B+4\"   DISABLED_style= \"max-width:90%; height:auto;\" > = Ann's age in 4 years<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=b+%2B+4 ALIGN=MIDDLE  ALT=\"b+%2B+4\"   DISABLED_style= \"max-width:90%; height:auto;\" > = Bill's age in 4 years<BR>\n" );
document.write( "given:<BR>\n" );
document.write( "(1) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=a+=+%287%2F10%29%2Ab ALIGN=MIDDLE  ALT=\"a+=+%287%2F10%29%2Ab\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "(2) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=a+%2B+4+=+%288%2F11%29%2A%28b+%2B+4%29 ALIGN=MIDDLE  ALT=\"a+%2B+4+=+%288%2F11%29%2A%28b+%2B+4%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "--------------------------------<BR>\n" );
document.write( "(1) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=a+=+%287%2F10%29%2Ab ALIGN=MIDDLE  ALT=\"a+=+%287%2F10%29%2Ab\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "and,<BR>\n" );
document.write( "(2) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=a+%2B+4+=+%288%2F11%29%2A%28b+%2B+4%29 ALIGN=MIDDLE  ALT=\"a+%2B+4+=+%288%2F11%29%2A%28b+%2B+4%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "Multiply both sides by <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=11 ALIGN=MIDDLE  ALT=\"11\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "(2) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=11a+%2B+44+=+8b+%2B+32 ALIGN=MIDDLE  ALT=\"11a+%2B+44+=+8b+%2B+32\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "Substitute (1) into (2)<BR>\n" );
document.write( "(2) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=11%2A%287%2F10%29%2Ab+%2B+44+=+8b+%2B+32 ALIGN=MIDDLE  ALT=\"11%2A%287%2F10%29%2Ab+%2B+44+=+8b+%2B+32\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "(2) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=77b+%2B+440+=+80b+%2B+320 ALIGN=MIDDLE  ALT=\"77b+%2B+440+=+80b+%2B+320\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "(2) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=3b+=+120 ALIGN=MIDDLE  ALT=\"3b+=+120\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "(2) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=b+=+40 ALIGN=MIDDLE  ALT=\"b+=+40\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "Bill is 40 now<BR>\n" );
document.write( "check answer:<BR>\n" );
document.write( "From (1),<BR>\n" );
document.write( "(1) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=a+=+%287%2F10%29%2A40 ALIGN=MIDDLE  ALT=\"a+=+%287%2F10%29%2A40\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "(1) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=a+=+28 ALIGN=MIDDLE  ALT=\"a+=+28\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "And, frm (2),<BR>\n" );
document.write( "(2) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=28+%2B+4+=+%288%2F11%29%2A%2840+%2B+4%29 ALIGN=MIDDLE  ALT=\"28+%2B+4+=+%288%2F11%29%2A%2840+%2B+4%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "(2) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=32+=+%288%2F11%29%2A%2840+%2B+4%29 ALIGN=MIDDLE  ALT=\"32+=+%288%2F11%29%2A%2840+%2B+4%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "(2) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=32+=+32 ALIGN=MIDDLE  ALT=\"32+=+32\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "OK\r<BR>\n" );
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document.write( " </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );