µ = 81
σ = 4
P ( X > 85 ) = P( (X-µ)/σ ≥ (85-81) / 4)
= P(Z > 1.000 ) = P( Z <
-1.000 ) = 0.1587
(answer)
The diameters of ball bearings are distributed normally. The mean diameter is 81 millimeters and the...
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