简便方法计算9.01×1.55+9.02×1.54+9.03×1.53+9.04×1.52

Question

简便方法计算9.01×1.55+9.02×1.54+9.03×1.53+9.04×1.52

Answer 1

9.01×1.55＋9.02×1.54＋9.03×1.53＋9.04×1.52
＝9.02×1.55＋9.02×1.54－0.01×1.55＋9.04×1.53＋9.04×1.52－0.01×1.53
＝9.02×﹙1.55＋1.54﹚＋9.04×﹙1.53＋1.52﹚－0.01×﹙1.55－1.53﹚
＝9.02×3.09＋9.04×3.05－0.01×0.02
＝9.04×3.09＋9.04×3.05－0.02×3.09－0.01×0.02
＝9.04×﹙3.09＋3.05﹚－0.02×﹙3.09－0.01﹚
＝9.04×6.14－0.02×3.08
＝9.04×6.14－0.01×6.16
＝9.04×6.14－0.01×6.14－0.01×0.02
＝6.14×﹙9.04－0.01﹚－0.01×0.02
＝6.14×9.03－0.01×0.02
＝6.14×9＋6.14×0.03－0.01×0.02
＝55.26＋0.1842－0.0002
＝55.444