Question

Could you please provide assistance with this question - I need to be able to use this in excel

The Langley tire company measures their tire strength on a scale from 1 to 10 They do this by randomly selecting three tires for each test period and destroy (ultimately determining their strength). Below is the results of this day's tests.

Hour	A	B	C
4	8	6	7
8	6	8	8
12	7	8	7
16	6	8	7

a.

Find the 3 sigma UCL and LCL for the mean and range charts.

b.

Is this process in statistical control? Why or why not?

Answer 1

Given data

Hour	A	B	C
4	8	6	7
8	6	8	8
12	7	8	7
16	6	8	7

Total no of sample (n)=12

mean of the sample

varience

Stadard deviation

now from the formula of we have

b)This process is a statistally controlled process because

A statistacally controlled process is a process in which the data we get in obserrvation will not exeed the UCL and lowers the LCL .data flows smoothly without showing any abnormal growth.

in this case we have UCL=8.90 and LCL=4.77

as we can see in all observation no data exceded the limit that means the process is a statistacally controlled process