简便计算是直接提取公约数3.6得3.6x(8.9-0.7)=3.6x8.2=3.6x8+3.6x0.2=28.8+0.72=29.52加油💪！
8.9ⅹ3.6一0.36ⅹ7=3.6ⅹ(8.9一0.7)=3.6x8.2=28.8十0.72=29.52
