Anonymous
Anonymous asked in 科學數學 · 6 years ago

急!!20點 統計學 常態分配與信賴區間

今在學校隨機抽取10名學生為樣本,調查其中餐費用平均80元,標準差15元,假設學校學生中餐費用為常態分配,試求該學校學生中餐平均費用之70% 的信賴區間。

麻煩請附上EXcel函數公式教我如何做!

1 Answer

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  • 慈信
    Lv 4
    6 years ago
    Favorite Answer

    n=10 , u=80 , σ=15 , α=0.3

    C.I : u ± Zα/2 * σ/√n = 80 ± 1.037 * 15/√10 = [ 75.081 , 84.919 ]

    C.I.下限 : NORM.INV(0.15,80,15/SQRT(10)) = 75.08376

    C.I.上限 : NORM.INV(0.85,80,15/SQRT(10)) = 84.91624

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