28.5×0.9+2.85用简便方法怎么计算

2025-06-21 05:00:29
推荐回答(1个)
回答1:

28.5×0.9+2.85
=2.85×10×0.9+2.85=2.85×9+2.85=2.85×(9+1)=2.85×10=28.5