Question

A canning company defines a "nonconformance" as an orange juice can whose diameter is beyond the upper specification limit.A manager at the canning company wants to monitor the number of such orange juice cans produced per day.Each day,an employee will randomly select 120 cans over a period of four weeks.The employee then determines and plots the number of nonconformance cans in each sample.The appropriate control chart is a(n):_________.

A) u-chart.
B) R-chart.
C) p-chart.
D) np-chart.

Answer 1

Option D. np-chart.

Step-by-step explanation:

An np-chart is an attributes control chart which is used with the data that is collected in subgroups that are the same size. Np-charts are used to show how the process (which is measured by the number of nonconforming items it produces) changes over time. The process attribute is always described in a yes/no, pass/fail, go/no go form.

In other words, an np-chart refers to a plot of number of defective pieces in a fixed sample size in the order of production. If the sample size is fixed, np-chart can be used. For instance, the number of incomplete accident reports in a constant daily sample of five would be plotted on an np-chart.