fangzhen

代码说明：

  赶火车过程仿真 一列火车从A站经过B站开往C站，某人每天赶往B站乘这趟火车。已知火车从A站到B站运行时间为均值30分钟、标准差为2分钟的正态随机变量.火车大约在下午1点离开A站。离开时刻的频率分布为 (Process simulation, a train to catch the train from A through B station station station bound for C, B Station tour someone rushed to the train every day. Known to the train station from station A to B as the average running time 30 minutes, standard deviation of 2 minutes of normal random variables. Trains leave about 1:00 pm A station. The frequency distribution for the leave time)