简便计算 帮我解 是0.25Ⅹ39+0.25 0.25Ⅹ3.2Ⅹ0.125
问题描述：
简便计算 帮我解 是0.25Ⅹ39+0.25 0.25Ⅹ3.2Ⅹ0.125
答
0.25Ⅹ39+0.25
=0.25Ⅹ39+0.25Ⅹ1
=0.25Ⅹ(39+1)
=1/4Ⅹ40
=10
0.25Ⅹ3.2Ⅹ0.125
=0.25Ⅹ4Ⅹ0.8Ⅹ0.125
=1Ⅹ0.1
=0.1