document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=184848>Question 184848</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Please help me with the following questions.I dont understand what Im doing.\r<BR>\n" );
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document.write( "In a survey of 75 consumers, 12 indicated that they were going to buy a new car, 18 said they were going to buy a new refrigerator, and 24 said they were going to buy a new washer. Of these, 6 were going to buy both a car and a refrigerator, 4 were going to buy a car and a washer, and 10 were going to buy a washer and a refrigerator. One person indicated that she was going to buy all three items. <BR>\n" );
document.write( "Construct a Venn diagram, label your diagram clearly.  Use your diagram to answer the following questions:<BR>\n" );
document.write( "(a)	How many were going to buy only a car? <BR>\n" );
document.write( "(b)	How many were going to buy only a washer? <BR>\n" );
document.write( "(c)	How many were going to buy only a refrigerator<BR>\n" );
document.write( "(d)	How many were going to buy a car and a washer but not a refrigerator? <BR>\n" );
document.write( "(e)	How many were going to buy none of these items? \r<BR>\n" );
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document.write( "Please help me </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #138714 by </B><A HREF=/tutors/aboutme.mpl?userid=josmiceli><B>josmiceli(19441)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=josmiceli><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=josmiceli><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=138714\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> What you have to draw is 3 interlocking circles with<BR>\n" );
document.write( "an area in the middle which is common to all 3.<BR>\n" );
document.write( "Kind of like the olympic rings.<BR>\n" );
document.write( "1 ring will be consumers who bought refrigerators<BR>\n" );
document.write( "1 ring will be consumers who bought cars<BR>\n" );
document.write( "1 ring will be consumers who bought washers<BR>\n" );
document.write( "All the small and big areas making up the rings adds up to<BR>\n" );
document.write( "the total number of people buying items <BR>\n" );
document.write( "Right away I'm told that the car ring contains 12 people,<BR>\n" );
document.write( "the fridge ring contains 18 people, and the washer ring<BR>\n" );
document.write( "contains 24 people<BR>\n" );
document.write( "What I do is label each ring just outside of it like this:<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=c=12 ALIGN=MIDDLE  ALT=\"c=12\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=f=18 ALIGN=MIDDLE  ALT=\"f=18\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=w=24 ALIGN=MIDDLE  ALT=\"w=24\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "Of these, 6 were going to buy both a car and a refrigerator<BR>\n" );
document.write( "Locate the small area where c and f overlap, and put a <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=6 ALIGN=MIDDLE  ALT=\"6\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "inside it.<BR>\n" );
document.write( "4 were going to buy a car and a washer.<BR>\n" );
document.write( "This is the area common to c and w. Put a 4 inside it<BR>\n" );
document.write( "10 were going to buy a washer and a refrigerator<BR>\n" );
document.write( "Label the intersection of w and f with a 10<BR>\n" );
document.write( "One person indicated that she was going to buy all three items. <BR>\n" );
document.write( "This last fact gives you all the answers. It's the key.<BR>\n" );
document.write( "The intersection of c and f = 6, but 1 of those is the last<BR>\n" );
document.write( "person, so 6 - 1 = 5 persons will buy ONLY both f and c.<BR>\n" );
document.write( "10 - 1 = 9 persons will buy ONLY both w and f.<BR>\n" );
document.write( "4 - 1 = 3 persons will buy ONLY both w and c.<BR>\n" );
document.write( "Now you should be able to label every area on the diagram<BR>\n" );
document.write( "(a) How many were going to buy only a car? 3<BR>\n" );
document.write( "(b) How many were going to buy only a washer? 11<BR>\n" );
document.write( "(c) How many were going to buy only a refrigerator 3<BR>\n" );
document.write( "(d) How many were going to buy a car and a washer but not a refrigerator? 3<BR>\n" );
document.write( "(e) How many were going to buy none of these items? 40<BR>\n" );
document.write( "I come up with a total of 35 persons buying items<BR>\n" );
document.write( "c = 3<BR>\n" );
document.write( "w = 11<BR>\n" );
document.write( "f = 3<BR>\n" );
document.write( "w+c  DISABLED_event_only=  3<BR>\n" );
document.write( "f+c  DISABLED_event_only=  5<BR>\n" );
document.write( "w+f  DISABLED_event_only=  9<BR>\n" );
document.write( "All 3 = 1<BR>\n" );
document.write( "------------<BR>\n" );
document.write( "35 total<BR>\n" );
document.write( "The trick is not to count the sme area twice.<BR>\n" );
document.write( "Hope I got the right answers and my method helps you  </SPAN>\n" );
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