Question 878744
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Hi
My recommendation would be an Excel electronic worksheet
0r something similar. Key is: (12.5-8.6)/2 = 1.95 and 8.6+1.95 = 10.55, for ex
x	n	 xn	x -17.43 n(x -17.43)^2	
10.55	13	137.15	-6.88	615.3472	
14.55	16	232.8	-2.88	132.7104	
18.55	5	92.75	1.12	6.272	
22.55	4	90.2	5.12	104.8576	
26.55	12	318.6	9.12	998.0928	
					
	50	871.5	5.6	1857.28 (sum)	
	mean	17.43		37.90367347	Variance sum/(n-1)
				6.156595932	SD (sqrt of variance)