(I2h Ad8 Mna) Homew
(I2h Ad8 Mna) Homew
(I2h Ad8 Mna) Homew
a) Do the data support the claim that the standard deviation of fill volume is less
than 1 ml? Use =0.05.
b) Find a 95% two-sided confidence interval on the standard deviation of fill
volume. (c) Does it seem reasonable to assume that fill volume has a normal
distribution?
5) A high-voltage power supply should have a nominal output voltage of 350 V. A
sample of four units is selected each day and tested for process-control purposes.
The data shown in Table 6E.2 give the difference between the observed reading on
each unit and the nominal voltage times ten; that is,
xi = (observed voltage on unit i - 350)10
x
a) Set up and R charts on this process. Is the process in statistical control?
b) If specifications are at 350 V 5 V, what can you say about process capability?
c) Is there evidence to support the claim that voltage is normally distributed?
6) The data shown in Table 6E.3 are the deviations from nominal diameter for holes
drilled in a carbon-fiber composite material used in aerospace manufacturing. The
values reported are deviations from nominal in ten-thousandths of an inch.