题目
The annual returns for a portfolio are normally distributed with an expected value of ￡50 million and a standard deviation of ￡25 million. Which of the following amounts is closest to the probability that the value of the portfolio one year from today will be between ￡91.13 million and ￡108.25 million?
选项
A.0.025
B.0.040
C.0.075
D.0.090
答案
B
解析
Calculate the standardized variable corresponding to the outcomes:「huixue_img/importSubject/1564169387349512192.png」The cumulative normal distribution gives cumulative probabilities of: F(1.645)=0.95 and F(2.33)=0.99 The probability that the outcome will lie between Z1 and Z2 is the difference: 0.99-0.95=0.04