求以下三道题的简便运算方法：5.7x1.25÷5.7x0.82.51x4-0.01÷0.255.4x[0.51÷（1.2-1.03）]

Question

求以下三道题的简便运算方法：5.7x1.25÷5.7x0.8 2.51x4-0.01÷0.25 5.4x[0.51÷（1.2-1.03）]

Answer 1

5.7x1.25÷5.7x0.8
＝﹙5.7÷5.7﹚×﹙1.25×0.8﹚
＝1×1
＝1
2.51x4-0.01÷0.25
＝﹙2.5＋0.01﹚×4－﹙0.01×4﹚÷﹙0.25×4﹚
＝10＋0.04－0.04
＝10
5.4x[0.51÷（1.2-1.03）]
＝5.4×﹙0.51÷0.17﹚
＝5.4×3
＝16.2