document.write( "Question 885582: Question 4: (1 point)\r
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\n" ); document.write( "\n" ); document.write( "At a tennis club, a 15,000 ft2 rectangular area is partitioned into three rectangular courts of equal size. A total of 800 feet of fencing is used to enclose the three courts, including the interior sides.\r
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\n" ); document.write( "\n" ); document.write( "Maple plot\r
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\n" ); document.write( "\n" ); document.write( "What are the possible dimensions, in feet, of the entire rectangular area?\r
\n" ); document.write( "\n" ); document.write( "Select all that apply.\r
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\n" ); document.write( "\n" ); document.write( " (a)
\n" ); document.write( "25feet by 600feet
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\n" ); document.write( " (b)
\n" ); document.write( "100feet by 150feet
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\n" ); document.write( " (c)
\n" ); document.write( "100feet by 300feet
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\n" ); document.write( " (d)
\n" ); document.write( "300feet by 50feet
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\n" ); document.write( " (e)
\n" ); document.write( "100feet by 50feet
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Algebra.Com's Answer #535316 by KMST(5328)\"\" \"About 
You can put this solution on YOUR website!
The answer they want is \"highlight%28%28d%29%29\" .
\n" ); document.write( "I would answer that and try hard not to say more.
\n" ); document.write( "Answer (b) Is also mathematically correct, and looks like a possibility for people not familiar with tennis.
\n" ); document.write( "That makes the question culturally biased, and makes the designer of the question look incompetent at math.
\n" ); document.write( "However, pointing out that may not gain you any points.
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\n" ); document.write( "MULTIPLE CHOICE STRATEGY:
\n" ); document.write( "Think efficiently, and do not waste time thinking too much and/or writing too many equations.\r
\n" ); document.write( "\n" ); document.write( "You can use the area information to quickly rule out (c) and (e):
\n" ); document.write( "The area for (c) is \"%28100feet%29%2A%28300feet%29=%2230%2C000%22\"\"ft%5E2\" , and
\n" ); document.write( "the area for (e) is \"%28100feet%29%2A%2850feet%29=%225%2C000%22\"\"ft%5E2\" .
\n" ); document.write( "Neither one of those is \"%2215%2C000%22\"\"ft%5E2\" , so (c) and (e) are not solutions.
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\n" ); document.write( "\"Make plot\" means draw a quick sketch.
\n" ); document.write( "It does not need to be a good drawing, and it cannot be to scale since you do not know the answer yet.
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\n" ); document.write( "The red lines represent the \"800\"\"feet\" of fencing, so
\n" ); document.write( "\"2%2Alength%2B4%2Awidth=800feet\"--->\"length%2B2width=400feet\"
\n" ); document.write( "How do choices (a), (b), and (d), fare against that requirement?
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\n" ); document.write( "For (a) \"2%2A25feet%2B600feet=50feet%2B600feet=650feet\" , so (a) does not work.
\n" ); document.write( "You did not even need to calculate because \"600feet\" length is by itself more than \"400feet\" .
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\n" ); document.write( "For (d) \"2%2A50feet%2B300feet=100feet%2B300feet=400feet\" , so \"highlight%28%28d%29%29\" is a solution.
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\n" ); document.write( "Since the problem is worth just one point, you do not need to think too long about it.
\n" ); document.write( "If all the choices are single answers,
\n" ); document.write( "as soon as you get an answer that everyone would like,
\n" ); document.write( "even if you have not tried the other options,
\n" ); document.write( "you choose that answer, and move on to another question.
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\n" ); document.write( "THINKING TOO MUCH:
\n" ); document.write( "For (b) \"2%2A100feet%2B150feet=200feet%2B150feet=350feet\" , does not work.
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\n" ); document.write( "However, \"2%2A150feet%2B100feet=300feet%2B100feet=400feet\" works, so (b) 100feet by 150feet could be a solution, if \"length=100feet\" and \"width=150\".
\n" ); document.write( "In the plot/sketch, \"length\" and \"width\" were just variable names representing the measurements of the two sides of the big rectangle.
\n" ); document.write( "It is not necessary that \"length%3Ewidth\" , or that \"length\" meant the longer side of that rectangular \"%2215%2C000%22\"\"ft%5E2\" area.
\n" ); document.write( "I bet the people who designed the question never thought of that.
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\n" ); document.write( "Answer (b) 100feet by 150feet is mathematically correct.
\n" ); document.write( "Unfortunately, \"length=100feet\" and \"width=150\" would mean that each court would be \"33%261%2F3\"\"ft\" by \"150\"\"ft\" , and that is too narrow and too long for a tennis court. (I looked it up).
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\n" ); document.write( "WRITING TOO MANY EQUATIONS:
\n" ); document.write( "\"L\"= one of the dimensions of the total area to be fenced, in feet.
\n" ); document.write( "\"W\"= the other dimension of the total area to be fenced, in feet.
\n" ); document.write( "\"L%2AW=15000\"<--->\"W=15000%2FL\" (because the area is 15,000 square feet).
\n" ); document.write( "\"2L%2B4W=800\"<--->\"L%2B2W=400\" (because 800ft is total amount of fence, and the sketch/plot shows that \"2L%2B4W\" is that length as a function of \"L\" and \"W\" ).
\n" ); document.write( "\"system%28L%2B2W=400%2CW=15000%2FL%29\"--->\"L%2B2%2815000%2FL%29=400\"--->\"L%2B30000%2FL=400\"--->\"L%5E2%2B30000L=400L\"--->\"L%5E2-400L%2B30000=0\"
\n" ); document.write( "Any way you solve that equation, you get two solutions:
\n" ); document.write( "either \"L=300\"-->\"W=15000%2F300\"--->\"W=50\" ,
\n" ); document.write( "or \"L=100\"-->\"W=15000%2F100\"--->\"W=150\" .
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