This assignment is optional and is worth 10 bonus points. In this assignment you'll create a p-chart to monitor the percentage of all paragraphs in a newspaper that contain errors. The situation: Newspapers strive for accuracy both in terms of content and grammar. One such paper, The Daily Planet, wants to monitor p, the percentage of all typeset paragraphs in the newspaper that contain at least one grammatical error. Each day for the past 25 days, Editor Perry White examines a random sample of 50 paragraphs in the paper and counts the number of paragraphs which have at least one grammatical error: 5, 6, 8, 7, 3, 12, 7, 6, 5, 4, 8, 3, 1, 7, 6, 8, 5, 4, 11, 7, 4, 9, 3, 4, 7 The above data have already been entered into column B of the "Data" sheet. Additional information and instructions are given on the "Data" sheet. Notes: a) Type your name and SFSU ID# in row 1 of the "Data" sheet. b) Anwer the questions in the spaces provided on the "Data" sheet. c) Save your Excel file as "A5-LastnameFirstname" and submit on Canvas by the due date. A 1 Name: 2 3 4 No. Samples B D E G H SFSU ID#: To Do: Save your Excel file as "AS-LastnameFirstname" 5 Sample Size p-bar= std. error= 6 7 Day Errors Pct. Errors LCL UCL CL 1 5 9 2 6 10 3 8 11 4 7 12 5 3 13 6 12 14 7 7 15 8 6 16 9 5 17 10 4 18 11 8 19 12 3 20 13 1 21 14 7 22 15 6 23 16 8 24 17 5 25 18 26 19 11 27 20 7 28 21 4 29 22 9 30 23 3 31 24 4 32 25 7 95.45% LCL 95.45% UCL K M N P R S a) Enter key input values in cells B4 and 55. b) Calculate the sample percentages in C8:C32 using cell formulas. c) Using cell formulas, calculate the sample average percentage of paragraphs with errors (p-bar) in cell E4, the standard error in cell E5, and the lower and upper control limits (LCL and UCL) in cells H4:H5 that correspond to 95.45% confidence interval limits. d) Keep 3 decimal places for p-bar, the standard error, LCL, and UCL. 1) Below row 33, make a line chart that plots the sample percentages, center line (CL), and control limits. Label the axes. To get the center line and control limits plotted on the same line chart with the sample percentages, you can simply repeat p-bar, LCL and UCL for each day, in cells D8:F32. Make your line chart big enough to be easily read. 2a) On which days does the sample % with errors fall above the UCL? 2b) On which days does the sample 96 with errors fall below the LCL?, 3) Has The Daily Planet's grammatical quality been in-control or out-of-control? Explain briefly. 4) Suppose now that each sample point above the UCL (only) can be explained by an assignable cause (e.g., copy editor Jimmy Olsen out sick). Temporarily delete the sample percentages that are above the UCL (but not those below the LCL) from the data set and let Excel recalculate the 95.45% control limits. In practice, these revised control limits would then be used to monitor future observations of the percentage of defective paragraphs. What is the: 4a) Revised p-bar? 4b) Revised std. error? 4c) Revised LCL? 4d) Revised UCL?