document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=30471>Question 30471</A>: <I><SPAN STYLE=\"word-break: break-all;\"> In What postive base B does the equation 4*12=103 for multiplication of base B hold? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #17113 by </B><A HREF=/tutors/aboutme.mpl?userid=longjonsilver><B>longjonsilver(2297)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=longjonsilver><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=longjonsilver><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=17113\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> the answer is base 5.\r<BR>\n" );
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document.write( "I am not sure if there is a \"proper\" way of figuring this out, using \"modulo\" maths, but here is my approach:\r<BR>\n" );
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document.write( "12<BR>\n" );
document.write( "x4<BR>\n" );
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document.write( "In base 10, we would say... what is 2x4? answer is 8.\r<BR>\n" );
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document.write( "In our base, the answer is still \"8\", but we will write it differently.\r<BR>\n" );
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document.write( "Seeing as how we have the number 4, the base must be base 4 or greater, so i started there:\r<BR>\n" );
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document.write( "base 4, the number 8 would be 20...no end \"3\" there. So, base 5...\r<BR>\n" );
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document.write( "base 5, the number \"8\" would be 13.. voila, a \"3\". So base 5 looks a good guess.\r<BR>\n" );
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document.write( "so, 2x4 is \"8\"...written as 3 with the 1 carried.\r<BR>\n" );
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document.write( "Now, 1x4 is 4 plus the carried 1 is 5. In base 5, 5 is written as \"10\"\r<BR>\n" );
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document.write( "So we have \"10\"...\"3\" --> 103.\r<BR>\n" );
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document.write( "Hope this explains it well enough for you.\r<BR>\n" );
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document.write( "jon.<BR>\n" );
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