有一类概率问题可以看成是由几个相互独立的事件进行“串联”或“并联”组成的.只要把“串联”看成“且”,“并联”看成“或”,再用概率有关的计算公式即可获解,请看几例: There is a class of probability problems that can be regarded as being made up of “serial” or “parallel” pairs of mutually independent events. As long as “concatenation” is regarded as “and”, “parallel” is regarded as “or”, and then the probability is used. The calculation formula can be solved. Please see a few examples: