(已解决)Form 5 Add Math Chapter 8的一些问题

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Tanonst

2012-8-25 10:59 PM

本帖最后由 Tanonst 于 2012-8-26 02:38 PM 编辑

Probability Distributions 的一些题目不是很清楚怎么做
就好象这几题

P(Z>k)=0.2574
P(Z<k)=0.6539
P(Z>k)=0.7136

要找出k的value

这类题目我不懂要怎么从那个Standard Normal Distribution Table 找出答案来
各位大大能帮小弟解决问题吗?

就要考SPM TRIAL了, 希望能快点掌握到Add Math的技巧

black7white

2012-8-25 11:25 PM

Probability Distributions 的一些题目不是很清楚怎么做
就好象这几题

P(Z>k)=0.2574
P(Zk)=0.7136

...
Tanonst 发表于 2012-8-25 10:59 PM

这个是我多年前学的，毕业多年但还记得

P(Z<k)=0.6539
直接看table找value

如果P(z>k)=n
就要1-n,再找value

草莓裙

2012-8-25 11:38 PM

area under bell shape graph=probability
the whole area under bell shape graph is symmetrical and the total area = 1
tat mean the highest probability =1
the horizontal axis is k-axis
the shaded region represent the probability

for P(Z>k)=0.2574,the probability is smaller than 0.5 (tat mean the value of k should be positive,since the bell-shape graph is half at the middle which k=0,)

to find the value of k,from ur standard ND table,the left hand side column + upper horizontal row represent ur k value,and the middle "group number" are the probability

不懂的话可以问youtube
我不是很懂要怎样在这里讲解