在除法里，被除数扩大15倍，除数缩小15倍，商不变．

3.87÷43{#blank#}1{#/blank#}38.7÷43

52÷4{#blank#}2{#/blank#}5.2÷0.4

25.8÷2{#blank#}3{#/blank#}25.8×0.5

14.2÷1.6{#blank#}4{#/blank#}14.2÷16

我发现：{#blank#}5{#/blank#}

× {#blank#}1{#/blank#}        ÷3{#blank#}2{#/blank#}        ×2{#blank#}3{#/blank#} ×4        ÷ {#blank#}4{#/blank#}

8.9×1.01{#blank#}1{#/blank#}8.9           19.6×1.3{#blank#}2{#/blank#}1.96×13

3.7×0.9{#blank#}3{#/blank#}3.7÷0.9        0.7×0.7{#blank#}4{#/blank#}0.7+0.7