A Quality Analyst wants to construct a control chart for determining whether five machines, all producing the same product, are under control with regard to a particular quality variable. Accordingly, four units of putputs from each machine are collected:

Machine	Measurement 1	Measurement 2	Measurement 3	Measurement 4
M1	45	43	43	39
M2	42	45	39	40
M3	40	45	43	41
M4	45	41	43	40
M5	40	40	42	45

Does this process appear to be out of control? If yes, identify a machine using the factors of three sigma control limits.

a.

M4

b.

M3

c.

M5

d.

M2

e.

Process is in Control

f.

M1