document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=315130>Question 315130</A>: <I><SPAN STYLE=\"word-break: break-all;\"> a two digit number is such that the product of its digit it equal to 20.if 9 is added to the number the digits interchange their places.find the number<BR>\n" );
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document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #225432 by </B><A HREF=/tutors/aboutme.mpl?userid=malaydassharma><B>malaydassharma(59)</B></A><img src=\"/images/stars/stars-08.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=malaydassharma><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=malaydassharma><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=225432\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> let x= once digit and y is tenth digit.<BR>\n" );
document.write( "Then , number is 10y+x<BR>\n" );
document.write( "So, if the digits interchange their places, then the number is 10x+y\r<BR>\n" );
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document.write( "now, <BR>\n" );
document.write( "xy=20 ....(i)\r<BR>\n" );
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document.write( "10y+x+9=10x+y<BR>\n" );
document.write( "or 9x-9y=9<BR>\n" );
document.write( "or x-y=1 ..(ii)\r<BR>\n" );
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document.write( "From (i) and (ii) , we get\r<BR>\n" );
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document.write( "x(x-1)=20=4X5<BR>\n" );
document.write( "x=4 or 5 , but as x-y=1 , then x=5 and y=4\r<BR>\n" );
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document.write( "The number is 45. </SPAN>\n" );
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