document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=20565>Question 20565</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Is the following true or false?<BR>\n" );
document.write( "The set of whole numbers is closed under subtraction<BR>\n" );
document.write( "The set of whole numbers is closed under multiplication<BR>\n" );
document.write( "The set of whole numbers is closed under division\r<BR>\n" );
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document.write( "Thanks,<BR>\n" );
document.write( "Teri </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #9921 by </B><A HREF=/tutors/aboutme.mpl?userid=askmemath><B>askmemath(368)</B></A><img src=\"/images/stars/stars-10.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=askmemath><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=9921\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> First of all,let us start be defining the term \"closed\"<BR>\n" );
document.write( "A set of numbers is said to be closed for an operation, if upon performing that operation between the numbers you get a member of that set.<BR>\n" );
document.write( "For e.g<BR>\n" );
document.write( "Consider the set of whole numbers. Whole numbers are (1,2,3,4,5......)<BR>\n" );
document.write( "Now,take any 2 numbers and add them. Say 5 and 6. The sum we get is 11 which as we know is a whole number.<BR>\n" );
document.write( "Now we can say that the set of Whole Numbers is closed under Addition.<BR>\n" );
document.write( "Consider Subtraction.<BR>\n" );
document.write( "6-5 = 1<BR>\n" );
document.write( "But 5-6 = -1 which is not a whole number.<BR>\n" );
document.write( "So  the set of Whole Numbers is NOT closed under Subtraction.\r<BR>\n" );
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document.write( "Can you try for Multiplication and Division? </SPAN>\n" );
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