. The data shown here are & and R values for 24 samples of size n = 5 taken from a process producing bearings. The mea-

surements are made on the inside diam-

eter of the bearing, with only the last three decimals recorded (i.c ., 34.5 should be 0.50345).

Sample Sample Number R

Number R

1 34.5 3

13 35.4 8

2 34,7 4

14 34.0 6

3 31.6 15 37.1 5

4 31.5 4

16 34.9 T

5 35.0 5

17 33.5 4

6 34.1 6

18 31.7 3

7 32.6 4

19 34.0 8

8 33.8 3

20 35.1 4

9 34.8 7

21 33.7 2

10 33.6 8

22 32.8 1

11 31.9 3

23 33.5 3

12 38.6 24 34.2

(a) Set up F and R charts on this process. Does the process seem to be in statistical control? If neces-

sary, revise the trial control limits.

(b) If specifications on this diameter are 0.5030 + 0,0010, find the percent-

age of nonconforming bearings pro-

duced by this process. Assume that diameter is normally distributed.