TABLE 10-13 A Quality Control Engineer Is in Charge of the Manufacture

question 32

Short Answer

TABLE 10-13
A quality control engineer is in charge of the manufacture of computer disks. Two different processes can be used to manufacture the disks. He suspects that the Kohler method produces a greater proportion of defects than the Russell method. He samples 150 of the Kohler and 200 of the Russell disks and finds that 27 and 18 of them, respectively, are defective. If Kohler is designated as "Group 1" and Russell is designated as "Group 2," perform the appropriate test at a level of significance of 0.01.
-Referring to Table 10-13, construct a 90% confidence interval estimate of the difference in proportion between the Kohler and Russell disks that are defective.

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Definitions:

Direct Labour Efficiency Variance

The difference between the actual number of labor hours worked and the standard hours expected, multiplied by the standard labor rate.

Direct Labour Hours

The total time labor directly involved in manufacturing a product or providing a service, often used for allocating labor costs to products or services.

Standard Hours

The set amount of time expected to be spent on a particular task, project, or to produce a certain quantity of goods.