document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1191782>Question 1191782</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Each of the 40 boys in a group plays at least one of the two games: Badminton(B) and<BR>\n" );
document.write( "Football(F). 21 play Badminton and 28 play Football. Let the number of boys who play both<BR>\n" );
document.write( "Badminton and Football be x.<BR>\n" );
document.write( "a. Draw a clearly labelled Venn diagram to illustrate this information.<BR>\n" );
document.write( "b.Hence, find<BR>\n" );
document.write( "i.The value of x,<BR>\n" );
document.write( "ii.The number of boys who play only Badminton but not Football. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #823617 by </B><A HREF=/tutors/aboutme.mpl?userid=ikleyn><B>ikleyn(52855)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=ikleyn><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=ikleyn><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=823617\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> .<BR>\n" );
document.write( "Each of the 40 boys in a group plays at least one of the two games: Badminton(B) and<BR>\n" );
document.write( "Football(F). 21 play Badminton and 28 play Football. Let the number of boys who play both<BR>\n" );
document.write( "Badminton and Football be x.<BR>\n" );
document.write( "a. Draw a clearly labelled Venn diagram to illustrate this information.<BR>\n" );
document.write( "b.Hence, find<BR>\n" );
document.write( "i.The value of x,<BR>\n" );
document.write( "ii.The number of boys who play only Badminton but not Football.<BR>\n" );
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document.write( "<PRE STYLE=\"white-space: pre-wrap; white-space: -moz-pre-wrap; white-space: -pre-wrap; white-space: -o-pre-wrap; word-wrap: break-word;\">\r\n" );
document.write( "Use the fundamental formula for the union of two subsets B and F of the given finite set\r\n" );
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document.write( "    n(B U F) = n(B) + n(F) - n(B ∩ F).\r\n" );
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document.write( "In your case,  n(B U F) = 40,  since each of the 40 boys in a group plays at least one of the two games,\r\n" );
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document.write( "and  x = n(B ∩ F).\r\n" );
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document.write( "Therefore,  40 = 21 + 28 - x,  which implies\r\n" );
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document.write( "    x = 21 + 28 - 40 = 49 - 40 = 9.\r\n" );
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document.write( "Thus 9 boys play both sports.\r\n" );
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document.write( "The number of those who play only Badminton, is  21 - 9 = 12.\r\n" );
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document.write( "To get it, we should subtract those who play both sports from those who play Badminton.\r\n" );
document.write( "</PRE>\r<BR>\n" );
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document.write( "Solved and explained.\r<BR>\n" );
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document.write( "To see many other similar &nbsp;(and different) &nbsp;solved problems, &nbsp;look into the lesson\r<BR>\n" );
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document.write( "&nbsp;&nbsp;&nbsp;&nbsp;- <A  rel=nofollow HREF=http://www.algebra.com/algebra/homework/word/misc/Counting-elements-in-sub-sets-of-a-given-finite-set.lesson>Counting elements in sub-sets of a given finite set</A>\r<BR>\n" );
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document.write( "in this site.\r<BR>\n" );
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document.write( "Learn the subject from there.\r<BR>\n" );
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document.write( " </SPAN>\n" );
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