3.12+3.12×9.9简便计算怎么做 紧急 答对了我再给赏20

问题描述:

3.12+3.12×9.9简便计算怎么做 紧急 答对了我再给赏20

3.12+3.12*9.9
=3.12+3.12*(10-0.1)
=3.12+3.12*10-3.12*0.1
=3.12+31.2-0.312
=34.32-0.312
=34.008