S = Sqrt [ D2 - n * (D / n)2 / n-1 ]
= Sqrt[ (148 - 6 * (24/6)2 / 5) ]
= 3.2249
Test statistics
t = (D / n) / ( S / sqrt(n) )
= (24/6) / (3.2249 / sqrt(6) )
= 3.0382
Data were collected on lost-time accidents (mean work-hours lost per month over a period of 1...
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