问题如下图:
选项:
A.
B.
C.
解释:
这道题目使用正态分布的区间来计算可以么,1.65对应的区间范围是0.9 那么0~1.65的距离就是0.9/2=0.45
NO.PZ2015120604000094 0.46. 0.45. C is correct. From the stanrnormstribution table, F(1.65) = 0.95. So P(0≤Z≤1.65) = F(1.65)-F(0) = 0.95-0.5 = 0.45. 如题。90%减去0左边的0.5,应该得出的是40%?
NO.PZ2015120604000094 老师,请问本题问的是p(z),记得老师上课讲过p(z)是求密度函数啊,不是累积函数啊,但本题答案是按照F(z)累积函数求面积方法求解的,有点糊涂了哈。
NO.PZ2015120604000094 0.46. 0.45. C is correct. From the stanrnormstribution table, F(1.65) = 0.95. So P(0≤Z≤1.65) = F(1.65)-Z(0) = 0.95-0.5 = 0.45. 1.65对应的不是90吗?
NO.PZ2015120604000094 0.46. 0.45. C is correct. From the stanrnormstribution table, F(1.65) = 0.95. So P(0≤Z≤1.65) = F(1.65)-Z(0) = 0.95-0.5 = 0.45.我记得老师讲的里面1.65是u+1.65✖️标准差。这个是90%,但这道题u没给,标准差也没给,怎么就算出来了呢?谢谢
0.46. 0.45. C is correct. From the stanrnormstribution table, F(1.65) = 0.95. So P(0≤Z≤1.65) = F(1.65)-Z(0) = 0.95-0.5 = 0.45.老师,这个思路错在哪