9667
統計 這題該如何解?
Asuume that a 90% confidence interval on the mean is to be constructed with a maximumerror of E .The population standard deviation is equal to 50. How large a sample is required if :1.X bar is to be within10 units of the population mean2.X bar is to be within15 units of the population mean3.X bar is to be within 5 units of the population mean有些字看不懂不知道在問什麼無法作答請高手大大幫個忙越詳細越好感激不盡
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舒凡很高興為您說明Asuume that a 90% confidence interval on the mean is to be constructed with a maximumerror of E .The population standard deviation is equal to 50. How large a sample is required if :假設90%的信賴區間
是建立在一個最大誤差E人口的標準差=50下列狀況
抽樣數應為多少計算公式:E=1/2X bar= Z(0.01/2)*50/√nZ(0.05)=1.6451.X bar is to be within10 units of the population mean10/2=1.645*50/√n
n=(16.45)^2=270.6=2712.X bar is to be within15 units of the population mean15/2=1.645*50/√n
n=(10.9667)^2=120.26=1213.X bar is to be within 5 units of the population mean5/2=1.645*50/√n
n=(32.9)^2=1082.4=1083檢視圖片
