Concept explainers
(a)
Interpretation: As there was a concern pertaining to the number of faults in the billing process of Data Tech Credit Card Service Company, the manager of customer service has done a random inspection on 250 statements, for errors, that has happened to wrong entries that involved penalty charges, account numbers, charges levied on interests and customer account transactions. If there are one or more the errors, in the heads mentioned above, then that statement is considered as a defect. The Table 3.5 represents the data collected from the study for the last 30 days. A p-chart for the billing process needs to be constructed.
Sample | Number of errors in Sample of 250 | |||||||||
1 − 10 | 3 | 8 | 5 | 11 | 7 | 1 | 12 | 9 | 0 | 8 |
11 − 20 | 3 | 5 | 7 | 9 | 11 | 3 | 2 | 9 | 13 | 4 |
21 - 30 | 12 | 10 | 6 | 2 | 1 | 7 | 10 | 5 | 8 | 4 |
Table 3.5
Concept Introduction: A process is analyzed between the limits of control and evaluated whether the same is under control or not, identifying the count of defects present. A p-chart reflects the proportion of defects that a process has.
(b)
Interpretation: As there was a concern pertaining to the number of faults in the billing process of Data Tech Credit Card Service Company, the manager of customer service has done a random inspection on 250 statements, for errors, that has happened to wrong entries that involved penalty charges, account numbers, charges levied on interests and customer account transactions. If there are one or more the errors, in the heads mentioned above, then that statement is considered as a defect. The Table 3.5 represents the data collected from the study for the last 30 days. Any non-random behavior in the billing process that would require management attention needs to be found out.
Sample | Number of errors in Sample of 250 | |||||||||
1 − 10 | 3 | 8 | 5 | 11 | 7 | 1 | 12 | 9 | 0 | 8 |
11 − 20 | 3 | 5 | 7 | 9 | 11 | 3 | 2 | 9 | 13 | 4 |
21 - 30 | 12 | 10 | 6 | 2 | 1 | 7 | 10 | 5 | 8 | 4 |
Table 3.5
Concept Introduction: A process is analyzed between the limits of control and evaluated whether the same is under control or not, identifying the count of defects present. A p-chart reflects the proportion of defects that a process has.
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