six sigma tutor help

3. Q The bore size of a component to be used in an assembly is a critical dimension. Random samples of 4 are chosen.

The summary information below is for 25 Samples.

                    The specification limits are 4.40.2 mm lumes

a.     Assuming the process is in control, estimate the process standard deviation

b.    Find the Xbar and R chart control limits

c.     What are your conclusion regarding the ability of the process to produce items conforming to specifications? Find Cp and Cpk.

d.    Assuming that if an item exceeds the upper specification limit it can be reworked and if it is below the lower limit it must be scrapped, what percent scrap and rework is the process now producing?

e.     It the process were centered on at u = 4.4, what would be the effect on the percent scrap or rework?

f.     The unit cost of scrap and rework are $2.40 and $0.75 respectively. The Daily production rate is 1200. Find the total cost of scrap and rework