To ensure the quality of microprocessor chips manufactured by Sigma Electronics,
ID: 405046 • Letter: T
Question
To ensure the quality of microprocessor chips manufactured by Sigma Electronics, the quality control department samples 100 chips produced each day. These chips are subjected to extreme operating conditions for several hours. At the end of the test, the numbers of failed chips are reported. Table 11.11 shows the results for the last 20 test runs. Create a p chart, then report if the production process is in control.
Table 11.11
Sample Number
Number of Failed Microprocessor Chips
1
3
2
0
3
2
4
1
5
4
6
9
7
2
8
5
9
4
10
6
11
0
12
3
13
5
14
2
15
4
Table 11.11
Sample Number
Number of Failed Microprocessor Chips
1
3
2
0
3
2
4
1
5
4
6
9
7
2
8
5
9
4
10
6
11
0
12
3
13
5
14
2
15
4
Explanation / Answer
we can use simple statistics to create a p chart with an upper control limit (UCL) and a lower control limit (LCL). We can draw these control limits on a graph and then plot the fraction defective of each individual sample tested. The process is assumed to be working correctly when the samples, which are taken periodically during the day, continue to stay between the control limits.Sample Number No.of chips inspected Number of Failed Microprocessor Chips Fraction defective 1 100 3 0.03 2 100 0 0 3 100 2 0.02 4 100 1 0.01 5 100 4 0.04 6 100 9 0.09 7 100 2 0.02 8 100 5 0.05 9 100 4 0.04 10 100 6 0.06 11 100 0 0 12 100 3 0.03 13 100 5 0.05 14 100 2 0.02 15 100 4 0.04 TOTAL 50 Total no.of samples tested = 1500
To construct the control chart, first calculate the overall fraction defective from all samples. This sets the centerline for the control chart. p = Total number of defects from all samples / Number of samples
To construct the control chart, first calculate the overall fraction defective from all samples. This sets the centerline for the control chart. p = Total number of defects from all samples / Number of samples Sample Number No.of chips inspected Number of Failed Microprocessor Chips Fraction defective 1 100 3 0.03 2 100 0 0 3 100 2 0.02 4 100 1 0.01 5 100 4 0.04 6 100 9 0.09 7 100 2 0.02 8 100 5 0.05 9 100 4 0.04 10 100 6 0.06 11 100 0 0 12 100 3 0.03 13 100 5 0.05 14 100 2 0.02 15 100 4 0.04 TOTAL 50 Total no.of samples tested = 1500
Related Questions
drjack9650@gmail.com
Navigate
Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.