0.25×3.9×4
=(4×0.25)×3.9
=1×3.9
=3.9
0.25×3.9×4=3.9
如果不简算,就是先计算0.25x3.9,也就是相当于(0.25x3.9)x4,简算,就是先计算0.25x4,即(0.25x4)x3-9,所以属于乘法结合律的运用,即0.25x3.9x4=(0.25x4)x3.9=3.9
0.25x3.9x4 = 0.25x4x3.9 = 1x3.9 = 3.9
解: 0.25×3.9×4=0.25×4×3.9=1×3.9=3.9,运用乘法交换率,希望可以帮到你