Business Statistics

670 Business Statistics

Copper sheet Defects

24 2

25 1

26 2

27 3

28 4

29 3

30 2

Solution Figure 17.31 exhibits c control chart for the data given in Table 17.15 produced

using SPSS

FIGURE 17.31

c control chart for

Example 17.8 produced using

SPSS

The centreline, upper control limit (UCL), and the lower control limit (LCL) can

be determined as below:

Centreline (CL) =

c

= 2.8

Upper control limit (UCL) =

3c c+

= 7.82

Lower control limit (LCL) =

3c c−

= –2.22 (=0)

Since the lower control limit cannot be negative, it is taken as zero.

SUmmarY|

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