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標 題統計題目?
發信站無名小站 (Fri Apr 14 20:53:04 2006)
轉信站ptt!Group.NCTU!grouppost!Group.NCTU!wretch
The efficacy of insecticides is often measured by the does necessary to kill a
certain percentage of insects. Suppose a certain dose of a new insecticide is
supposed to kill 80% the insects that receive it. To test the claim, 25
insects are exposed to the insecticide.
a.If the insecticide really kills 80% of the exposed insects, what is the
probability that fewer then 15 die?
我是算出 0.0062 不知道對不對
b.If you observed such a result, what would you conclude about the new
insecticide? Explain your logic.
沒有給α, 不知道要如何下手.
The 2112 members responding had a salary distribution with a 20th percentile
of $35100 ; a median of $50000 ; and an 80th percentile of $73000.
a.Use this information to determine the minimum sample size that could be used
in next year to estimate the mean salary of the members to within $2000 with
98% confidence.
b.Explain how you estimated the standard deviation required for the sample
size calculation.
c.List any assumptions you make.
感謝!
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夫兵者不祥之器物或惡之故有道者不處君子居則貴左用兵則貴右兵者不祥之器非君子
之器不得已而用之恬淡為上勝而不美而美之者是樂殺人夫樂殺人者則不可得志於天下
矣吉事尚左凶事尚右偏將軍居左上將軍居右言以喪禮處之殺人之眾以哀悲泣之戰勝以
喪禮處之道常無名樸雖小天下莫能臣侯王若能守之萬物將自賓天地相合以降甘露民莫
之令而自均始制有名名亦既有夫亦將知止知止可以不殆譬道之SciEdu.NCTU.edu.tw海