document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1111392>Question 1111392</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A number between 20 and 30 and is three times the sum of its digits. What is the number?\r<BR>\n" );
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document.write( "How do you work this problem </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #726402 by </B><A HREF=/tutors/aboutme.mpl?userid=greenestamps><B>greenestamps(13200)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=greenestamps><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=greenestamps><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=726402\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <br><BR>\n" );
document.write( "Algebraically, if x is the units digit, then the number is 20+x and the sum of its digits is 2+x.  So<br><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=20%2Bx+=+3%282%2Bx%29 ALIGN=MIDDLE  ALT=\"20%2Bx+=+3%282%2Bx%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=20%2Bx+=+6%2B3x ALIGN=MIDDLE  ALT=\"20%2Bx+=+6%2B3x\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=14+=+2x ALIGN=MIDDLE  ALT=\"14+=+2x\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x+=+7 ALIGN=MIDDLE  ALT=\"x+=+7\"   DISABLED_style= \"max-width:90%; height:auto;\" ><br><BR>\n" );
document.write( "The units digit is 7; the number is 27.<br><BR>\n" );
document.write( "Using algebra to solve this problem is good practice with algebra; but the problem is easily solved with a little mental arithmetic.<br><BR>\n" );
document.write( "The number is 3 times the sum of its digits, so it is a multiple of 3.<br><BR>\n" );
document.write( "The only  multiples of 3 between 20 and 30 are 21, 24, and 27.<br><BR>\n" );
document.write( "Only 27 satisfies the condition that it is 3 times the sum of its digits.<BR>\n" );
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