請問 organisms,的意思

Biology as a separate science was developed in the nineteenth century as scientists discovered that organisms shared fundamental characteristics. Biology is now a standard subject of instruction at schools and universities around the world, and over a million papers are published annually in a wide array of biology and medicine journals.

一、設X~N(3,0.16),求以下各題之機率值或Y值:

1. 由此常態母體中抽出 n=4 的隨機樣品:

(a) P( <2.5)=?

(b) P( >Y)=0.03 的Y=?

2. 由此常態母體中抽出 n=15 的隨機樣品:

(c) P(2.8 < <3.8)=?

(d) P(Y< <3)=0.17的Y=?

二、某大學學校學生心理測驗分數呈常態分布,平均為500,標準差為50,試問:

1. 某位學生的分數是高於510的機率為何? 低於400?

2. 若隨機抽出16位學生,求他們的平均分數( )介於480到520的機率為何?

3. 以500為中心, 有90%的機率此16名樣本的平均分數會介於多少之間?

4. 有80%的機率此16名樣本的平均分數會高於多少?

...

Most biological sciences are specialized disciplines. Traditionally, they are grouped by the type of organism being studied: botany, the study of plants; zoology, the study of animals; and microbiology, the study of microorganisms. The fields within biology are further divided based on the scale at which organisms are studied and the methods used to study them: biochemistry examines the fundamental chemistry of life; molecular biology studies the complex interactions of systems of biological molecules; cellular biology examines the basic building block of all life, the cell; physiology examines the physical and chemical functions of the tissues and organ systems of an organism; and ecology examines how various organisms and their environment interrelate.

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  • 1 decade ago
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    一、設Xi~N( 3,0.16),求以下各題之機率值或Y值:

    1. 由此常態母體中抽出 n = 4 的隨機樣品:

    X-bar~N( 3,0.16/4),其中 X-bar = ΣXi,i = 1, 2, 3, 4.

    (a) P( X-bar < 2.5 )

    2.5 - 3

    = P( Z < -----------------)

    √( 0.16/4)

    = P( Z < -2.5 )

    = 0.0062

    (b) P( X-bar > Y )

    Y - 3

    = P( Z > --------------- )

    √( 0.16/4)

    = P( Z > 1.8808 )

    = 0.03

    ∴ Y = 3 √( 0.16/4) 1.8808 = 3.3762

    2. 由此常態母體中抽出 n = 15 的隨機樣品:

    X-bar~N( 3,0.16/15),其中 X-bar = ΣXi,i = 1, 2, …, 15.

    (c) P( 2.8 < X-bar <3.8 )

    = P( X-bar < 3.8 ) - P( X-bar < 2.8 )

    3.8 - 3 2.8 - 3

    = P( Z < ----------------- ) - P( Z < ------------------ )

    √( 0.16/15) √( 0.16/15)

    = P( Z < 7.7460 ) - P( Z < -1.9365 )

    = 1.0000 – 0.0246

    = 0.9736

    (d) P( Y< X-bar <3 )

    = P( X-bar < 3 ) - P( X-bar < Y )

    3 – 3 Y - 3

    = P( Z < ------------------- ) - P( Z < ------------------- )

    √( 0.16/15) √( 0.16/15)

    = P( Z < 0 ) - P( Z < -0.4399 )

    = 0.5 – 0.33

    = 0.17

    ∴ Y = 3 √( 0.16/15) -0.4399 = 2.9546

    二、某大學學校學生心理測驗分數呈常態分布,平均為500,標準差為50,試問:

    1. 某位學生的分數是高於510的機率為何?低於400?

    X1~N( 500,502)

    (a) P( X1 > 510 )

    510 - 500

    = P( Z > ----------------- )

    50

    = P( Z > 0.2 )

    = 0.4207

    (b) P( X1 < 400 )

    400 - 500

    = P( Z < ----------------- )

    50

    = P( Z < -2 )

    = 0.0228

    2. 若隨機抽出16位學生,求他們的平均分數介於480到520的機率為何?

    X-bar~N( 500,502/16),其中 X-bar = ΣXi,i = 1, 2, …, 16.

    P( 480 < X-bar < 520 )

    = P( X-bar < 520 ) – P( X-bar < 480 )

    520-500 480-500

    = P( Z < ---------------- ) - P( Z < ----------------- )

    √( 502/16) √( 502/16)

    = P( Z < 1.6 ) - P( Z < -1.6 )

    = 0.9452 – 0.0548

    = 0.8904

    Source(s): 我的求學過程…
  • 1 decade ago

    *生物,有機體

    *機體,有機組織

    Factories and cities are more complex organisms than self-sufficient villages.

    工廠和城市是較自給自足的村莊更為複雜的社會組織。

    主要是<有機体>的意思

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