(99999+9999+999+99+9)乘1\2

问题描述:

(99999+9999+999+99+9)乘1\2

(99999+9999+999+99+9)乘1\2
=(100000+10000+1000+100)/2+5/2
=111100/2+2.5
=55550+2.5
=55552.5