4.4. A transmission main shaft bearing retainer carried specifications of 2.8341–2.8351 in. In a production run, measurements were made in 0.0001 in. from the ‘‘nominal’’ 2.8346 in.

Thus, the specifications were 5 to þ5 in the coded units. The following data on averages and ranges were recorded. Plot the two running trend charts, x-bars above the corresponding R’s.

x-bar þ3.4 þ1.4 þ5.6 2.6 þ1.2 2.0 8.2 5.8 7.8 4.0 R 6 3 24 1 6 3 1 6 2 6 x-bar 5.0 10.2 þ2.2 þ0.8 þ1.0 þ1.6 7.8 3.8 2.0 0 R 5 9 7 8 2 4 3 7 2 0