Answer:
a) 0.667
b) Yes
Explanation:
Data provided in the question:
Mean = 0.04
Standard Deviation = 0.003
Upper Specification Limit, USL = 0.046
Lower Specification Limit, LSL = 0.034
Now,
a) Capability Index is given as:
Cp = [tex]\frac{(USL-LSL)}{(6\sigma)}[/tex]
or
Cp = [tex]\frac{(0.046-0.034)}{(6\times0.003)}[/tex]
or
Cp = 0.667
Also,
Cpk = min([tex]\frac{(USL-Mean)}{(3\sigma)},\frac{(Mean-LSL)}{(3\sigma)}[/tex]
or
Cpk = min([tex]\frac{(0.046-0.04)}{(3\times0.003)},\frac{(0.04-0.034)}{(3\times0.003)}[/tex]
or
Cpk = min( 0.667 , 0.667 )= 0.667
Since,
Cp and Cpk are same in this case
therefore, it is ideal condition and process is capable
b) yes