说明：  VB求多个进度条的平均值源代码，可以计算出多个进度条的平均值，可以用在安装程序或是其它运算类程序中，告之用户程序运行的状态，提升软件体验。
(VB progress bar for more than the average of the source code, you can calculate the average number of progress bar, the installation process can be used in computing or other type of procedure, the user will run the state, enhance the software experience.)