步骤1.将无限循环小数分为2个部分,以你给的0.3454545...45为例,将其分0.3+0.04545...45这2个部分.步骤2.将这2个部分分别化成分数,0.3=3/10,0.0454545...45的划分方法.先设它为a,那么就有：10a=0.454545...451000a=45...