A factory collected data on the number of nonconforming parts to construct an np-chart. 15 samples of size 150 were collected. They determined that the average fraction was non-conforming as pbar=0.045. During production, a sample of 150 parts was taken, of which 18 were non-conforming. At the time this sample was taken: a. the upper control limit was 0.12 b. the lower control limit was 0 c. the sample was outside the control limits d. the sample was within the control limits.
1. A factory collected data on the number of nonconforming parts to construct an np-chart. 15 samples of size 150 were collected. They determined that the average fraction was non-conforming as pbar=0.045. During production, a sample of 150 parts was taken, of which 18 were non-conforming. At the time this sample was taken:
a. the upper control limit was 0.12
b. the lower control limit was 0
c. the sample was outside the control limits
d. the sample was within the control limits.
2. A control chart was in control, but the operator adjusted the process anyway. What is this called?
a. common cause variation
b. special cause variation
c. overcontrol
d. undercontrol
3. A control chart was out of control, but the operator failed to adjust the process. What is this called?
a. common cause variation
b. undercontrol
c. overcontrol
d. special cause variation
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