Table $7.1$ Factors for Calculating Three- Sigma Limits for The $\overline { \bar { X } }$

Table $7.1$
Factors for Calculating Three- Sigma Limits for the $\overline { \bar { X } }$ - chart and $R$ -chart


-Historically, the average diameter of the holes drilled has been 0.25 cm and the average range has been 0.1 cm. Determine the central line and upper and lower control limits for an $\bar { X -}$ and an R- chart, assuming samples of size 8 will be taken. Use Table 7.1.For the $\bar { X -}$ chart, what is the value of the $\text { LCL } \bar { X } ?$

A) less than or equal to 0.10
B) greater than 0.10 but less than or equal to 0.19
C) greater than 0.19 but less than or equal to 0.29
D) greater than 0.29