巧算.0.11+0.12+0.13.+0.18+0.19

问题描述:

巧算.0.11+0.12+0.13.+0.18+0.19

0.11+0.12+0.13.+0.18+0.19
=(0.11+0.19)x9÷2
=0.3x9÷2
=1.35