The Areas of the two triangles poly2 and poly1; respectively, are equal to half their Z and Normal Probabilities Values. Type values: (.2222 -- 100) or Z values: 1/Z (.01 -- 4.5) into input box sigma. Additionally: Normal Probabilities are equal to : Pr = (Area of Z triangle/ Area of Normal Probabilities)* Z Values PrN = (poly1/poly2)*Z ( Formula in Red ) Notice the Length of the Red Line is (.8424) , while my constant is (.8433) with the Error Function is: (erf. (1) = .8427)
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