(1+0.56+0.67)×(0.56+0.67+78)-(1+0.56+0.67+78)×(0.56+0.67)计算 简便

问题描述:

(1+0.56+0.67)×(0.56+0.67+78)-(1+0.56+0.67+78)×(0.56+0.67)计算 简便