Charts

1. The following measurements represent the length (in cm) of the electrical contacts of relays in samples of size 5, taken hourly from the operating process. Create the X- bar and R charts and decide if the process is in control.

Hour i X1 X2 X3 X4 X5 1 1.9890 2.1080 2.0590 2.0110 2.0070 2 1.8410 1.8900 2.0590 1.9160 1.9800 3 2.0070 2.0970 2.0440 2.0810 2.0510 4 2.0940 2.2690 2.0910 2.0970 1.9670 5 1.9970 1.8140 1.9780 1.9960 1.9830 6 2.0540 1.9700 2.1780 2.1010 1.9150 7 2.0920 2.0300 1.8560 1.9060 1.9750 8 2.0330 1.8500 2.1680 2.0850 2.0230 9 2.0960 2.0960 1.8840 1.7800 2.0050 10 2.0510 2.0380 1.7390 1.9530 1.9170 11 1.9520 1.7930 1.8780 2.2310 1.9850 12 2.0060 2.1410 1.9000 1.9430 1.8410 13 2.1480 2.0130 2.0660 2.0050 2.0100 14 1.8910 2.0890 2.0920 2.0230 1.9750 15 2.0930 1.9230 1.9750 2.0140 2.0020 16 2.2300 2.0580 2.0660 2.1990 2.1720 17 1.8620 2.1710 1.9210 1.9800 1.7900 18 2.0560 2.1250 1.9210 1.9200 1.9340 19 1.8980 2.0000 2.0890 1.9020 2.0820 20 2.0490 1.8790 2.0540 1.9260 2.0080

2. Following is the number of defects in daily samples (n=100) in January. Create the P and C charts and decide if the process is in control.

Sample Day Number of Defects Sample Day Number of Defects i Xi i Xi 1 6 16 6 2 8 17 4 3 8 18 6 4 13 19 8 5 6 20 2 6 6 21 7 7 9 22 4 8 7 23 4 9 1 24 2 10 8 25 1 11 5 26 5 12 2 27 15 13 4 28 1 14 5 29 4

15 4 30 1 31 5