document.write( "Question 1205795: What is the median of 80,80,80,80,80,85,85,85,85,85,90,90,90,90,90\r
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Algebra.Com's Answer #842835 by math_tutor2020(3816)\"\" \"About 
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\n" ); document.write( "Answer: 85\r
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\n" ); document.write( "\n" ); document.write( "Explanation\r
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\n" ); document.write( "\n" ); document.write( "Method 1\r
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\n" ); document.write( "\n" ); document.write( "The first task is to sort the values. Thankfully that has already been done for us.
\n" ); document.write( "Always make sure the values are sorted before attempting to find the median.\r
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\n" ); document.write( "\n" ); document.write( "The original string of values
\n" ); document.write( "80,80,80,80,80,85,85,85,85,85,90,90,90,90,90
\n" ); document.write( "rewrites to
\n" ); document.write( "80,80,80,80,80,
\n" ); document.write( "85,85,85,85,85,
\n" ); document.write( "90,90,90,90,90
\n" ); document.write( "which I think is easier to see how many items there are. This block of values is 3 items tall and 5 items across. There are 3*5 = 15 values total.\r
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\n" ); document.write( "\n" ); document.write( "n = 15 is the sample size.
\n" ); document.write( "n/2 = 15/2 = 7.5 which rounds to 8
\n" ); document.write( "The median is in slot 8
\n" ); document.write( "7 values are below it, and 7 values are above it
\n" ); document.write( "7+1+7 = 15 values total\r
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\n" ); document.write( "\n" ); document.write( "The value in slot 8 is 85. It's the 3rd copy of \"85\" in the second row of this block:
\n" ); document.write( "80,80,80,80,80,
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\n" ); document.write( "90,90,90,90,90
\n" ); document.write( "Or you can return back to the original string of values to count out 8 positions from the left.\r
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\n" ); document.write( "\n" ); document.write( "Method 2\r
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\n" ); document.write( "\n" ); document.write( "Chop off the first and last values of
\n" ); document.write( "80,80,80,80,80,85,85,85,85,85,90,90,90,90,90
\n" ); document.write( "to get
\n" ); document.write( "80,80,80,80,80,85,85,85,85,85,90,90,90,90,90
\n" ); document.write( "which cleans up to
\n" ); document.write( "80,80,80,80,85,85,85,85,85,90,90,90,90\r
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\n" ); document.write( "\n" ); document.write( "Repeat the process again to go from
\n" ); document.write( "80,80,80,80,85,85,85,85,85,90,90,90,90
\n" ); document.write( "to
\n" ); document.write( "80,80,80,85,85,85,85,85,90,90,90\r
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\n" ); document.write( "\n" ); document.write( "Keep this process going until either (a) we end up with one value or (b) we end up with 2 values
\n" ); document.write( "80,80,80,85,85,85,85,85,90,90,90
\n" ); document.write( "80,80,85,85,85,85,85,90,90
\n" ); document.write( "80,85,85,85,85,85,90
\n" ); document.write( "85,85,85,85,85
\n" ); document.write( "85,85,85
\n" ); document.write( "85
\n" ); document.write( "We see that 85 is the middle most value.\r
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\n" ); document.write( "\n" ); document.write( "Or what we can do is cross off say 3 items at a time from each endpoint.
\n" ); document.write( "This is to help speed things up.
\n" ); document.write( "80,80,80,80,80,85,85,85,85,85,90,90,90,90,90
\n" ); document.write( "80,80,80,80,80,85,85,85,85,85,90,90,90,90,90
\n" ); document.write( "80,80,85,85,85,85,85,90,90
\n" ); document.write( "80,80,85,85,85,85,85,90,90
\n" ); document.write( "85,85,85\r
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\n" ); document.write( "\n" ); document.write( "Note: If you end up with 2 values tied for the middle, then take the midpoint of them. This occurs only when the sample size is an even number.
\n" ); document.write( "The midpoint formula is (p+q)/2 where p and q are the middle most values.\r
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\n" ); document.write( "\n" ); document.write( "Method 3\r
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\n" ); document.write( "\n" ); document.write( "Use software such as a speadsheet or online calculator.
\n" ); document.write( "This method doesn't have much to explain about it, other than it's something I only recommend as a way to check your answer.
\n" ); document.write( "It's best to know how to find the median by hand.
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