简便计算:100+20+4+0.8+0.16+0.032+0.0064

问题描述:

简便计算:100+20+4+0.8+0.16+0.032+0.0064

124.9984你可以把这几个数看成是首项为0.0063,末项为100,公比为5的等比数列
以上回答你满意么?

100+20+4+0.8+0.16+0.032+0.0064
=100+20+4+(0.8+0.16)+0.032+0.0064
=124+(0.96+0.0064)+0.032
=124+(0.9664+0.032)
=124+0.9984
=124.9984