The width of a slot of a duralumin forging is (in inches) normally distributed with μ= 0.9000 and σ = 0.0030. The specification
limits were given as 0.9000 ±0.0050. Show your calculations. Draw normal curves wherever appropriate. a) What percentage of forgings will be defective?
b) What is the maximum allowable value of σ that will permit no more than 1 in 100 defectives when the widths are normally distributed with μ = 0.9000 and σ (revised value)?