document.write( "Question 656178: 1. Find the correlation coefficient for the data.
\n" ); document.write( " 2. Find the equation for the regression line for the data, and predict the final grade of a student who misses 3.5 days.\r
\n" ); document.write( "\n" ); document.write( "Number of Absences ....... Final Grade
\n" ); document.write( " 0 ....................... 100
\n" ); document.write( " 1 ....................... 92
\n" ); document.write( " 2 ....................... 83
\n" ); document.write( " 3 ....................... 78
\n" ); document.write( " 4 ....................... 66
\n" ); document.write( " 5 ....................... 51\r
\n" ); document.write( "\n" ); document.write( "I don't know where to begin, I am running out of time. I hope someone can help! \n" ); document.write( "
Algebra.Com's Answer #409391 by ewatrrr(24785)\"\" \"About 
You can put this solution on YOUR website!
 
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document.write( "Hi,
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document.write( "Don't know what You have been using to determine  standard deviationetc in general:
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document.write( "If you have a TI 83 calculator,might recommend this tutorial site:
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document.write( "http://www.tc3.edu/instruct/sbrown/ti83/regress.htm
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document.write( "\"r%5Bxy%5D=s%5Bxy%5D%2Fs%5Bx%5Ds%5By%5D\" where 
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document.write( "s[x]= sqrt\"%28sum%28%28x%5Bi%5D-m%5Bx%5D%29%5E2%29%2F%28n-1%29%29\" and s[y] = sqrt\"%28sum%28%28y%5Bi%5D-m%5By%5D%29%5E2%29%2F%28n-1%29%29\"
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document.write( "and \"s%5Bxy%5D+=+%28sum%28%28x%5Bi%5D-m%5Bx%5D%29%28y%5Bi%5D-m%5By%5D%29%29%2F%28n-1%29%29\" 
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document.write( "In the normal Work Up using an Excel Worksheet, there is a need to sum (xi - 2.5)(yi - 78.2) as well 
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document.write( "       (xi-2.5)^2 (yi-78.2)^2 (xi-2.5)(yi-78.2)
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document.write( "	6.25	475.24	-54.5
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document.write( "	2.25	190.44	-20.7
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document.write( "	0.25	14.44	-1.9
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document.write( "	0.25	0.04	-0.1
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document.write( "	2.25	148.84	-18.3
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document.write( "	6.25	739.84	-68
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document.write( "Sum	17.5	1568.84	-163.5
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document.write( "     \"s%5Bx%5D+=1.87\" \"+s%5By%5D+=17.71\" \"s%5Bxy%5D+=++-32.7\"
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document.write( "		33.14	
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document.write( "\"r+=+-32.7%2F%281.87%2A17.71%29\" = -32.7/33.14 = -.9867
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document.write( "Regression Line 1s:  y = ax + b,  where
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document.write( "a =  
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document.write( " and \"b+=+m%5By%5D+-++a%2Am%5Bx%5D\"
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document.write( "a = -163.5/17.5 = -9.34
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document.write( "\"b+=+78.2+-+%28-9.34%2A2.5%29\" = 100.5
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document.write( "y = -9.34x + 100.5
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