document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=257495>Question 257495</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Which set of numbers is not closed under multiplication? odd integers, even integers, prime numbers, or rational numbers. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #189417 by </B><A HREF=/tutors/aboutme.mpl?userid=drk><B>drk(1908)</B></A><img src=\"/images/stars/stars-12.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=drk><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/images/nopicture.jpg><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=189417\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Primes are not closed under multiplication.<BR>\n" );
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document.write( "Look at each separately:<BR>\n" );
document.write( "odd integers: odd x odd = odd [closed]<BR>\n" );
document.write( "even integers: even x even = even [closed]<BR>\n" );
document.write( "prime numbers: prime x prime = composite [NOT closed]<BR>\n" );
document.write( "rational numbers: fraction x fraction = fraction [closed] </SPAN>\n" );
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