document.write( "Question 1171027: The local bakery bakes more than a thousand 1-pound loaves of bread daily, and the weights of these loaves varies. The mean weight is 1.9 lb. and 4 oz., or 975 grams. Assume the standard deviation of the weights is 26 grams and a sample of 35 loaves is to be randomly selected.\r
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document.write( "(b) Find the mean of this sampling distribution. (Give your answer correct to nearest whole number.)\r
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document.write( "(c) Find the standard error of this sampling distribution. (Give your answer correct to two decimal places.)\r
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document.write( "(d) What is the probability that this sample mean will be between 965 and 985? (Give your answer correct to four decimal places.)\r
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document.write( "(e) What is the probability that the sample mean will have a value less than 967? (Give your answer correct to four decimal places.)\r
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document.write( "(f) What is the probability that the sample mean will be within 3 grams of the mean? (Give your answer correct to four decimal places.) \n" );
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Algebra.Com's Answer #850999 by CPhill(1959)![]() ![]() You can put this solution on YOUR website! Let's solve this problem step-by-step.\r \n" ); document.write( "\n" ); document.write( "**Given Information:**\r \n" ); document.write( "\n" ); document.write( "* Population mean (μ) = 975 grams \n" ); document.write( "* Population standard deviation (σ) = 26 grams \n" ); document.write( "* Sample size (n) = 35\r \n" ); document.write( "\n" ); document.write( "**(b) Find the Mean of the Sampling Distribution**\r \n" ); document.write( "\n" ); document.write( "The mean of the sampling distribution of the sample mean (μx̄) is equal to the population mean (μ).\r \n" ); document.write( "\n" ); document.write( "* μx̄ = μ = 975\r \n" ); document.write( "\n" ); document.write( "Therefore, the mean of the sampling distribution is 975.\r \n" ); document.write( "\n" ); document.write( "**(c) Find the Standard Error of the Sampling Distribution**\r \n" ); document.write( "\n" ); document.write( "The standard error (σx̄) is the standard deviation of the sampling distribution of the sample mean. It's calculated as:\r \n" ); document.write( "\n" ); document.write( "* σx̄ = σ / √n \n" ); document.write( "* σx̄ = 26 / √35 \n" ); document.write( "* σx̄ ≈ 26 / 5.9161 \n" ); document.write( "* σx̄ ≈ 4.3946\r \n" ); document.write( "\n" ); document.write( "Rounded to two decimal places, the standard error is 4.39.\r \n" ); document.write( "\n" ); document.write( "**(d) Probability that the Sample Mean is Between 965 and 985**\r \n" ); document.write( "\n" ); document.write( "We need to find P(965 < x̄ < 985). First, we need to convert the sample means to z-scores:\r \n" ); document.write( "\n" ); document.write( "* z₁ = (965 - 975) / 4.39 = -10 / 4.39 ≈ -2.28 \n" ); document.write( "* z₂ = (985 - 975) / 4.39 = 10 / 4.39 ≈ 2.28\r \n" ); document.write( "\n" ); document.write( "Now, we need to find P(-2.28 < Z < 2.28).\r \n" ); document.write( "\n" ); document.write( "* P(Z < 2.28) ≈ 0.9887 \n" ); document.write( "* P(Z < -2.28) ≈ 0.0113\r \n" ); document.write( "\n" ); document.write( "Therefore, P(-2.28 < Z < 2.28) = P(Z < 2.28) - P(Z < -2.28) ≈ 0.9887 - 0.0113 = 0.9774\r \n" ); document.write( "\n" ); document.write( "**(e) Probability that the Sample Mean is Less Than 967**\r \n" ); document.write( "\n" ); document.write( "We need to find P(x̄ < 967). First, we need to convert 967 to a z-score:\r \n" ); document.write( "\n" ); document.write( "* z = (967 - 975) / 4.39 = -8 / 4.39 ≈ -1.82\r \n" ); document.write( "\n" ); document.write( "Now, we need to find P(Z < -1.82).\r \n" ); document.write( "\n" ); document.write( "* P(Z < -1.82) ≈ 0.0344\r \n" ); document.write( "\n" ); document.write( "**(f) Probability that the Sample Mean is Within 3 Grams of the Mean**\r \n" ); document.write( "\n" ); document.write( "We need to find P(975 - 3 < x̄ < 975 + 3), which is P(972 < x̄ < 978).\r \n" ); document.write( "\n" ); document.write( "* z₁ = (972 - 975) / 4.39 = -3 / 4.39 ≈ -0.68 \n" ); document.write( "* z₂ = (978 - 975) / 4.39 = 3 / 4.39 ≈ 0.68\r \n" ); document.write( "\n" ); document.write( "We need to find P(-0.68 < Z < 0.68).\r \n" ); document.write( "\n" ); document.write( "* P(Z < 0.68) ≈ 0.7517 \n" ); document.write( "* P(Z < -0.68) ≈ 0.2483\r \n" ); document.write( "\n" ); document.write( "Therefore, P(-0.68 < Z < 0.68) = P(Z < 0.68) - P(Z < -0.68) ≈ 0.7517 - 0.2483 = 0.5034\r \n" ); document.write( "\n" ); document.write( "**Answers:**\r \n" ); document.write( "\n" ); document.write( "(b) 975 \n" ); document.write( "(c) 4.39 \n" ); document.write( "(d) 0.9774 \n" ); document.write( "(e) 0.0344 \n" ); document.write( "(f) 0.5034 \n" ); document.write( " \n" ); document.write( " |