document.write( "Question 198485: Thank you so much this teacher is picking me a part with these problem please help.\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( ") In a survey of 100 consumers, 33 indicated that they were going to buy a new car, 18 said they were going to buy a new refrigerator, and 34 said they were going to buy a new washer. Of these, 7 were going to buy both a car and a refrigerator, 15 were going to buy a car and a washer, and 9 were going to buy a washer and a refrigerator. Three consumers indicated that they were going to buy all three items. \r
\n" ); document.write( "\n" ); document.write( "Construct a Venn diagram, label your diagram clearly.
\n" ); document.write( "Use your diagram to answer the following questions:\r
\n" ); document.write( "\n" ); document.write( "(a) How many were going to buy only a car?
\n" ); document.write( "(b) How many were going to buy only a washer?
\n" ); document.write( "(c) How many were going to buy only a refrigerator
\n" ); document.write( "(d) How many were going to buy a car and a washer but not a refrigerator?
\n" ); document.write( "(e) How many were going to buy none of these items\r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "thank you so much
\n" ); document.write( "

Algebra.Com's Answer #149026 by josmiceli(19441)\"\" \"About 
You can put this solution on YOUR website!
(1) Draw a circle that represents the consumers that are going to buy
\n" ); document.write( "a new car. What I do sometimes to avoid confusion is to label the
\n" ); document.write( "circle right in the center with a \"c\"
\n" ); document.write( "Don't even worry about numbers at this point.
\n" ); document.write( "(2) Some consumers are going to buy a refrigerator, and, reading
\n" ); document.write( "ahead, some of these are also buying a new car. So, now draw a
\n" ); document.write( "circle that intersects the refrigerator circle, and label it in the center
\n" ); document.write( "with a small \"r\" Where the circle intersects the new car circle,
\n" ); document.write( "label that intersection with \"c x r\"
\n" ); document.write( "Make sure you leave some room for other circles. Don't worry about numbers.
\n" ); document.write( "(3) This is the tricky part. A third circle will represent the
\n" ); document.write( "washing machine buyers. Some of these are new car buyers also, and
\n" ); document.write( "some are refrigerator buyers, so this new circle will intersect both
\n" ); document.write( "the \"c\" circle and the \"r\" circle. Label the new circle \"w\"
\n" ); document.write( "Label the intersection with \"c\", \"c x w\"
\n" ); document.write( "Label the intersection with \"r\", \"r + w\"
\n" ); document.write( "(4) There is one last bit of information: some of the washing machine
\n" ); document.write( "buyers are buying all three things. This is the small intersection of
\n" ); document.write( "the three circles. If your picture doesn't have this small intersection,
\n" ); document.write( "redraw it. It will be \"w + c + r\". I just draw an arrow pointing to
\n" ); document.write( "it and put this label outside the circles.
\n" ); document.write( "(5) If the drawing is right, and you can make sense of it, then you
\n" ); document.write( "can proceed with the numbers and answer any question about it.
\n" ); document.write( "The labels you have are:
\n" ); document.write( "\"c\" ALL the new car buyers
\n" ); document.write( "\"r\" ALL the refrigerator buyers
\n" ); document.write( "\"c x r\" ALL those who will buy both car and refrigerator
\n" ); document.write( "\"w x c\" ALL those who will buy washing machine and car
\n" ); document.write( "\"w x r\" ALL those who will buy washing machine and refrigerator
\n" ); document.write( "\"w x c x r\" those who will buy all three things
\n" ); document.write( "The really tricky part is to realize that intersections like
\n" ); document.write( "\"c x r\" also INCLUDE the ones that buy all three.
\n" ); document.write( "Try to see the circles two at a time, ignoring the third.
\n" ); document.write( "I hope this helps:
\n" ); document.write( "(A) How many were going to buy only a car? That means no washer, no frige
\n" ); document.write( "I'm told that 7 will buy \"c x r\" and 15 will buy \"c x w\"
\n" ); document.write( "\"33+-+7+-+15+=+11\"
\n" ); document.write( "Tricky part: I an subtracting the \"c x r x w = 3\" group
\n" ); document.write( "they are being subtracted twice, so to subtract them once, I need to add
\n" ); document.write( "back \"3\" so, \"33+-+7+-+15+%2B+3+=+14\"
\n" ); document.write( "14 will buy only a car
\n" ); document.write( "-------------------------
\n" ); document.write( "(B) Those only buying a washer will not buy car or frige.
\n" ); document.write( "I need to subtract from \"w+=+34\" the intersections \"w x c\"
\n" ); document.write( "and \"w x r\", so I get \"34+-+15+-+9+=+10\", but remember, by
\n" ); document.write( "subtracting these two groups, I am subtracting \"w x c x r\" twice
\n" ); document.write( "so, I'll add back 3 once
\n" ); document.write( "\"34+-+15+-+9+%2B+3+=+13\"
\n" ); document.write( "13 will buy only a washer
\n" ); document.write( "---------------------------
\n" ); document.write( "(C) How many were going to buy only a refrigerator?
\n" ); document.write( "I need to subtract from \"r\" the intersections \"r x w\" and \"r x c\"
\n" ); document.write( "\"18+-+9+-+7+=+12\", again, I am subtracting \"c x r x w\" twice,
\n" ); document.write( "so I'll add it back once. \"18+-+9+-+7+%2B+3+=+5\"
\n" ); document.write( "5 will buy only a frige
\n" ); document.write( "---------------------------
\n" ); document.write( "(D) How many were going to buy a car and a washer but not a refrigerator?
\n" ); document.write( "\"c x w = 15\", but some of those will buy friges. How many? It's
\n" ); document.write( "the ones who will buy \"c x r x w\", so subtract 3
\n" ); document.write( "\"15+-+3+=+12\"
\n" ); document.write( "12 will buy \"c x w\" but not \"r\"
\n" ); document.write( "----------------------------
\n" ); document.write( "(E) How many were going to buy none of these items?
\n" ); document.write( "Not an easy question. What I have to do is add up the contents
\n" ); document.write( "of the three circles WITHOUT overlaps, that is not counting
\n" ); document.write( "anything twice.
\n" ); document.write( "I can make use of the questions I've answered.
\n" ); document.write( "ONLY \"c\" plus ONLY \"w\" plus ONLY \"r\" = \"14+%2B+13+%2B+5+=+32\"
\n" ); document.write( "OK, but this ignores all the intersections, so I have to add in
\n" ); document.write( "\"c x w\" PLUS \"c x r\" PLUS \"r x w\" = \"7+%2B+15+%2B+9+=+31\", but
\n" ); document.write( "by doing this, I have added \"c x r x w\" three times, so I need to
\n" ); document.write( "subtract it twice. \"7+%2B+15+%2B+9+-+3+-+3+=+25\"
\n" ); document.write( "And \"32+%2B+25+=+57\" so, there are 57 buyers without counting
\n" ); document.write( "anyone twice. There were 100 consumers surveyed, so \"100+-+57+=+43\"
\n" ); document.write( "43 will buy none of the items
\n" ); document.write( "----------------------------
\n" ); document.write( "Chcking my answer, If I add up
\n" ); document.write( "ONLY \"c\" PLUS \"r\" PLUS ONLY \"w\" PLUS \"c x w\" MINUS \"c x r x w\", then I
\n" ); document.write( "should get the result \"57\"
\n" ); document.write( "ONLY \"c\" = 14
\n" ); document.write( "\"r\" = 18
\n" ); document.write( "ONLY \"w\" = 13
\n" ); document.write( "\"c x w\" = 15
\n" ); document.write( "\"c x r x w = 3
\n" ); document.write( "\"14+%2B+18+%2B+13+%2B+15+-+3+=+57\"
\n" ); document.write( "OK \r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "
\n" );