document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1116804>Question 1116804</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Three newspapers A, B and C are published in<BR>\n" );
document.write( "a certain city. It is estimated from a survey<BR>\n" );
document.write( "that of the adult population : 20% read A,<BR>\n" );
document.write( "16% read B, 14% read C, 8% read both A and<BR>\n" );
document.write( "B, 5% read both A and C, 4% read both B and<BR>\n" );
document.write( "C, 2% read all three. Find what percentage<BR>\n" );
document.write( "read at least one of the newspapers?<BR>\n" );
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document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #731709 by </B><A HREF=/tutors/aboutme.mpl?userid=ikleyn><B>ikleyn(52788)</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=731709\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> .<BR>\n" );
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( "The percentage read at least one of the newspapers = (0.2 + 0.16 + 0.14 - 0.08 - 0.05 - 0.04 + 0.02)*100 = 35%.\r\n" );
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document.write( "    The first approximation is to add 20%, 16% and 14%.   (1) \r\n" );
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document.write( "    But in this way we count elements/(readers) in each intersection  AB, AC and AB twice.\r\n" );
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document.write( "    Therefore, we subtract 8%, 5% and 4%.                 (2)\r\n" );
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document.write( "    But in this way, we loose everything/(everybody) in the intersection ABC  (because we counted it/(them) thrice first in the step (1), \r\n" );
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document.write( "    and then excluded it/(them) thrice in the step (2). )\r\n" );
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document.write( "    Therefore, we add 2% as the last correction step.\r\n" );
document.write( "</PRE>\r<BR>\n" );
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document.write( "------------------------<BR>\n" );
document.write( "See the lessons\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( "&nbsp;&nbsp;&nbsp;&nbsp;- <A  rel=nofollow HREF=https://www.algebra.com/algebra/homework/word/misc/Advanced-probs-counting-elements-in-sub-sets-of-a-given-finite-set.lesson>Advanced problems on 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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