Could you use data from column A

Question 2 A fabricator has decided to add a shrinkage allowance to a panel to try to achieve an accurate result for the dimensions of the panel. The fabricator has also decided that the maximum percentage of panels requiring to be re-worked to correct the final dimension must be below 10% of all panels produced. Using the data assigned to you in the table over the page, calculate the mean error on the panel dimension without shrinkage allowance and the percentage of panels that are likely to be out of tolerance. State then whether the shrinkage allowance added to the panel is likely to be sufficient to achieve the desired accuracy, indicating how you have made that judgement. Calculate also whether the expected number of rejections remains within the limit specified (less than 10%) following addition of the shrinkage allowance. Standard normal distribution tables are provided on Canvas. Hint: the addition of the shrinkage allowance changes the cumulative mean error values of the processes but not the cumulative variance. Number of plates Number of stiffeners Mean and variance of process errors in mm Proposed shrinkage allowance mm Upper Tolerance mm Lower Tolerance mm Plate cutting mean Plate cutting variance Plate fairing mean Plate fairing variance Butt Weld shrinkage mean Butt Weld shrinkage variance Stiffener Weld shrinkage mean Stiffener weld shrinkage variance A 2 5 -0.2 0.1 1 0.5 -0.5 0.1 -0.5 0.1 2.4 2 -4 B 3 5 -0.5 0.1 1 0.5 -0.5 0.1 -0.5 0.1 3 2 -5 C 3 6 -0.2 0.1 1 0.5 -0.5 0.1 -0.5 0.1 2.6 2 -4