document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=419831>Question 419831</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Assist me with this difficult homework problem:\r<BR>\n" );
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document.write( "1. A survey of 51 pet owners revealed that 24 owned dogs, 28 owned cats, 11 owned turtles, 12 owned both dogs and cats, 7 owned both dogs and turtles, 3 owned both cats and turtles, and 2 owned all three. Find the number of pet owners who owned none of the three lovely animals.<BR>\n" );
document.write( "The answer is not 26. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #293516 by </B><A HREF=/tutors/aboutme.mpl?userid=richard1234><B>richard1234(7193)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=richard1234><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=richard1234><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=293516\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> By the Inclusion-Exclusion principle,\r<BR>\n" );
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document.write( "N = Dog + Cat + Turtle - Dog&#8745;Cat - Dog&#8745;Turtle - Cat&#8745;Turtle + Dog&#8745;Cat&#8745;Turtle\r<BR>\n" );
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document.write( "where Dog represents the number of dog owners, etc. and N represents the number of people who own at least one of the three.\r<BR>\n" );
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document.write( "N = 24 + 28 + 11 - 12 - 7 - 3 + 2 = 43\r<BR>\n" );
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document.write( "So, 43 people own at least one of the three animals. Therefore, 51-43 = 8 people do not own any of the three. </SPAN>\n" );
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