document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=908907>Question 908907</A>: <I><SPAN STYLE=\"word-break: break-all;\"> The sum of the digits of a certain two-digits number is 7. Reversing its digits increases the number by 9 what is the number ? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #551398 by </B><A HREF=/tutors/aboutme.mpl?userid=MathLover1><B>MathLover1(20849)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=MathLover1><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=MathLover1><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=551398\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <BR>\n" );
document.write( "Let's call the first digit \"<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=D ALIGN=MIDDLE  ALT=\"D\"   DISABLED_style= \"max-width:90%; height:auto;\" >\". Then the second digit must be <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=7-D ALIGN=MIDDLE  ALT=\"7-D\"   DISABLED_style= \"max-width:90%; height:auto;\" >, so that the two digits add up to <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=7 ALIGN=MIDDLE  ALT=\"7\"   DISABLED_style= \"max-width:90%; height:auto;\" >. \r<BR>\n" );
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document.write( " The value of the original number is ten times the tens digit, plus the units digit (for example, 48 is 4*10+8). \r<BR>\n" );
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document.write( "So, the original number is <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=10D+%2B+%287-D%29 ALIGN=MIDDLE  ALT=\"10D+%2B+%287-D%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >. \r<BR>\n" );
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document.write( "When you reverse the digits, you get <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=10%287-D%29+%2B+D ALIGN=MIDDLE  ALT=\"10%287-D%29+%2B+D\"   DISABLED_style= \"max-width:90%; height:auto;\" >. If this is <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=9 ALIGN=MIDDLE  ALT=\"9\"   DISABLED_style= \"max-width:90%; height:auto;\" > greater, then: <BR>\n" );
document.write( " <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=10%287-D%29+%2B+D+=+9+%2B+10D%2B%287-D%29+ ALIGN=MIDDLE  ALT=\"10%287-D%29+%2B+D+=+9+%2B+10D%2B%287-D%29+\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( " Solving this for <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=D ALIGN=MIDDLE  ALT=\"D\"   DISABLED_style= \"max-width:90%; height:auto;\" > gives us:<BR>\n" );
document.write( " <BR>\n" );
document.write( " <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=10%287-D%29+%2B+D+=+9+%2B+10D%2B%287-D%29+ ALIGN=MIDDLE  ALT=\"10%287-D%29+%2B+D+=+9+%2B+10D%2B%287-D%29+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( " <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=70+-+10D+%2B+D+=+9+%2B+10D+%2B+7+-+D+ ALIGN=MIDDLE  ALT=\"70+-+10D+%2B+D+=+9+%2B+10D+%2B+7+-+D+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( " <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=70+-+9D+=+9+%2B+9D+%2B+7 ALIGN=MIDDLE  ALT=\"70+-+9D+=+9+%2B+9D+%2B+7\"   DISABLED_style= \"max-width:90%; height:auto;\" > <BR>\n" );
document.write( " <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=70+=+9+%2B+18D+%2B+7+ ALIGN=MIDDLE  ALT=\"70+=+9+%2B+18D+%2B+7+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( " <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=61+=+18D+%2B+7 ALIGN=MIDDLE  ALT=\"61+=+18D+%2B+7\"   DISABLED_style= \"max-width:90%; height:auto;\" > <BR>\n" );
document.write( " <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=54+=+18D+ ALIGN=MIDDLE  ALT=\"54+=+18D+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( " <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=D+=+3 ALIGN=MIDDLE  ALT=\"D+=+3\"   DISABLED_style= \"max-width:90%; height:auto;\" > \r<BR>\n" );
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document.write( " This means the other digit has to be <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=4 ALIGN=MIDDLE  ALT=\"4\"   DISABLED_style= \"max-width:90%; height:auto;\" >. So the number is <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=34 ALIGN=MIDDLE  ALT=\"34\"   DISABLED_style= \"max-width:90%; height:auto;\" >. <BR>\n" );
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