document.write( "Question 852643: I am having trouble finding the answer to E and F in this problem. could you show me how to do letter E using the formula and also letter F.\r
\n" ); document.write( "\n" ); document.write( "The following are scores on a test in a math class.\r
\n" ); document.write( "\n" ); document.write( "67 89 94 55 76 71 66 87 69 74 99
\n" ); document.write( "84 55 42 68 77 90 88 81 78 65 79
\n" ); document.write( "98 64 77 70 85 89 92 72 61 94 83\r
\n" ); document.write( "\n" ); document.write( "a. Find the mean.
\n" ); document.write( " I have the mean as 2539/33= 76.9393
\n" ); document.write( " would you round this to the whole number?
\n" ); document.write( "b. Find the median.
\n" ); document.write( " I have the median as 77
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\n" ); document.write( "\n" ); document.write( "c. Find the mode.\r
\n" ); document.write( "\n" ); document.write( " i have the mode as 55,77,89\r
\n" ); document.write( "\n" ); document.write( "d. Find the range.
\n" ); document.write( " I have the range as 57\r
\n" ); document.write( "\n" ); document.write( "e. Find the standard deviation.\r
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\n" ); document.write( "\n" ); document.write( "f. How many of the scores are within one standard deviation of the mean?
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Algebra.Com's Answer #513573 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( "My point in doing the following is to encourage You to use a spreadsheet or Calculator
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document.write( "The IMPORTANT thing is to relatively easily find the standard deviation, 
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document.write( "so as to not forget the purpose of doing so in the process.
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document.write( "	m	(x-µ)	(x-µ)^2	
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document.write( "42	76.94	-34.94	1220.804	
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document.write( "55	76.94	-21.94	481.364	
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document.write( "55	76.94	-21.94	481.364	
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document.write( "61	76.94	-15.94	254.084	
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document.write( "64	76.94	-12.94	167.444	
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document.write( "65	76.94	-11.94	142.564	
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document.write( "66	76.94	-10.94	119.684	
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document.write( "67	76.94	-9.94	98.804	
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document.write( "68	76.94	-8.94	79.924	
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document.write( "69	76.94	-7.94	63.044	
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document.write( "70	76.94	-6.94	48.164	
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document.write( "71	76.94	-5.94	35.284	
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document.write( "72	76.94	-4.94	24.404	
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document.write( "74	76.94	-2.94	8.644	
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document.write( "76	76.94	-0.94	0.884	
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document.write( "77	76.94	0.06	0.004	
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document.write( "77	76.94	0.06	0.004	
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document.write( "78	76.94	1.06	1.124	
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document.write( "79	76.94	2.06	4.244	
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document.write( "81	76.94	4.06	16.484	
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document.write( "83	76.94	6.06	36.724	
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document.write( "84	76.94	7.06	49.844	
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document.write( "85	76.94	8.06	64.964	
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document.write( "87	76.94	10.06	101.204	
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document.write( "88	76.94	11.06	122.324	
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document.write( "89	76.94	12.06	145.444	
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document.write( "89	76.94	12.06	145.444	
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document.write( "90	76.94	13.06	170.564	
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document.write( "92	76.94	15.06	226.804	
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document.write( "94	76.94	17.06	291.044	
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document.write( "94	76.94	17.06	291.044	
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document.write( "98	76.94	21.06	443.524	
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document.write( "99	76.94	22.06	486.644	
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document.write( "76.93939394	        5823.879  sum	
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document.write( "			181.9962125 =  sum /(33-1)= Variance	
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document.write( "			13.4905971 = (sqrt of Variance) = SD = 13.5
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document.write( "f.How many of the scores are within one standard deviation of the mean?
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document.write( " Those scores between 76.9-13.5   and 76.9+13.5 
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document.write( "         0r  between 63.4  and 90.4  (Quite a number of them)
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document.write( "For the normal distribution: 
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document.write( "one  standard deviation from the mean accounts for about 68.2% of the set 
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document.write( "two standard deviations from the mean account for about 95.4%
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document.write( "and three standard deviations from the mean account for about 99.7%.
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document.write( "Important to Understand z -values as they relate to the Standard Normal curve:
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document.write( "Below:  z = 0, z = ± 1, z= ±2 , z= ±3 are plotted.  
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document.write( "Note: z = 0 (x value the mean) 50% of the area under the curve is to the left and %50 to the right
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