document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=426602>Question 426602</A>: <I><SPAN STYLE=\"word-break: break-all;\"> is 43 a prime number? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #296743 by </B><A HREF=/tutors/aboutme.mpl?userid=htmentor><B>htmentor(1343)</B></A><img src=\"/images/stars/stars-12.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=htmentor><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=htmentor><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=296743\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> We need to check if the number is divisible by anything other than 1 and 43.<BR>\n" );
document.write( "Since it is odd, it is not divisible by 2, which means it is not divisible by 4, 6, or 8 (and if it were, it wouldn't be prime, anyway!)<BR>\n" );
document.write( "Is it divisible by 3? No. 43/3 = 14, remainder 1<BR>\n" );
document.write( "It is not divisible by 5, since it does not end in 0 or 5.<BR>\n" );
document.write( "Is it divisible by 7? No. 43/7 = 6, remainder 1<BR>\n" );
document.write( "Since it is not divisible by 3, it is not divisible by 9.<BR>\n" );
document.write( "Therefore, the number is prime.  <BR>\n" );
document.write( "Note that we could have stopped checking at 7, since 7*7 = 49 > 43. </SPAN>\n" );
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