document.write( "Question 1172781: What should the control limits be placed in the design of the process sets alpha = 0.01 with the following parameters (assume that the sample size condition has been verified)?
\n" ); document.write( "(a) mu.png= 100,sigma.png= 20, and n = 25 cases per batch\r
\n" ); document.write( "\n" ); document.write( "(b) mu.png= 2000,sigma.png= 2000, and n = 100 cases per batch
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Algebra.Com's Answer #850805 by CPhill(1987)\"\" \"About 
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To determine the control limits for an X-bar chart, we need to calculate the upper control limit (UCL) and the lower control limit (LCL). We'll use the following formula:\r
\n" ); document.write( "\n" ); document.write( "* UCL = μ + Z(α/2) * (σ / √n)
\n" ); document.write( "* LCL = μ - Z(α/2) * (σ / √n)\r
\n" ); document.write( "\n" ); document.write( "Where:\r
\n" ); document.write( "\n" ); document.write( "* μ = population mean
\n" ); document.write( "* σ = population standard deviation
\n" ); document.write( "* n = sample size
\n" ); document.write( "* Z(α/2) = the Z-score corresponding to the desired significance level (alpha).\r
\n" ); document.write( "\n" ); document.write( "Given that alpha = 0.01, we need to find the Z-score for alpha/2 = 0.005. This means we are looking for the Z-score that leaves 0.005 in the upper tail of the standard normal distribution. Using a Z-table or calculator, we find that Z(0.005) ≈ 2.576.\r
\n" ); document.write( "\n" ); document.write( "**a. μ = 100, σ = 20, n = 25**\r
\n" ); document.write( "\n" ); document.write( "1. **Calculate the standard error of the mean (SEM):**
\n" ); document.write( " * SEM = σ / √n = 20 / √25 = 20 / 5 = 4\r
\n" ); document.write( "\n" ); document.write( "2. **Calculate the control limits:**
\n" ); document.write( " * UCL = 100 + 2.576 * 4 = 100 + 10.304 ≈ 110.30
\n" ); document.write( " * LCL = 100 - 2.576 * 4 = 100 - 10.304 ≈ 89.70\r
\n" ); document.write( "\n" ); document.write( "Therefore, the control limits for (a) are approximately 89.70 and 110.30.\r
\n" ); document.write( "\n" ); document.write( "**b. μ = 2000, σ = 2000, n = 100**\r
\n" ); document.write( "\n" ); document.write( "1. **Calculate the standard error of the mean (SEM):**
\n" ); document.write( " * SEM = σ / √n = 2000 / √100 = 2000 / 10 = 200\r
\n" ); document.write( "\n" ); document.write( "2. **Calculate the control limits:**
\n" ); document.write( " * UCL = 2000 + 2.576 * 200 = 2000 + 515.2 ≈ 2515.2
\n" ); document.write( " * LCL = 2000 - 2.576 * 200 = 2000 - 515.2 ≈ 1484.8\r
\n" ); document.write( "\n" ); document.write( "Therefore, the control limits for (b) are approximately 1484.8 and 2515.2.
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