Answer:
Sample number 3
Step-by-step explanation:
From the given information:
Sample Service life(hours) Total Mean(X)
1 2 3 4
1 495 500 505 500 2000 500
2 525 515 505 515 2060 515
3 470 480 460 470 1880 470
Total =
Mean =
Thus;
To plot on an X_Bar chart, we have:
Sample Mean (X) UCL LCL
1 500 520 480
5 515 520 480
6 470 520 480
The x-Bar chart is shown in the image attached below. From the image, we realize that the average service life for sample number 3 occurs to be out of the statistical control.
Permutation is different from combination because in combination the order is not a factor in considering the possible ways while permutation considers order as a factor. we are asked in this problem to evaluate 3P0 which is equal to 1.
9=3^2
3^(2x)=(3^2)^(3x-4)
3^(2x)=3^(6x-8)
2x=6x-8
0=4x-8
8=4x
2=x