Quiz: Demonstration problem on text page 119
The number of defectives too wide is found by entering the normal table (p. 737) at Z = (USL - m)/ s = ( 3.008 - 3.001) / 0.003 » 2.33 which yields the probability area 0.9901
So the probability of defectives too wide is 1 - 0.9901 = 0.0099 So 0.99% will be too wide