题目
Consider a stock with an initial price of $100. Its price one year from now is given by S=100e^r, where the rate of return r is normally distributed with a mean of 0.1 and a standard deviation of 0.2. With 95% confidence, after rounding, S will be between:
选项
A.$67.57 and $147.99
B.$70.80 and $149.20
C.$74.68 and $163.56
D.$102.18 and $119.53
答案
C
解析
The 95% confidence interval for r is - 0.292 to 0.492: r=0.1-(0.2×1.96)=- 0.2920 or r=0.1 (0.2 × 1.96)=0.4920 The 95% confidence interval for S is $74.68 to $163.56:「huixue_img/importSubject/1564169385726316544.png」