一个因数扩大10倍，另一个因数不变，积扩大了{#blank#}2{#/blank#}倍．

2×1.001{#blank#}1{#/blank#}2            {#blank#}2{#/blank#}         0.2×0.8{#blank#}3{#/blank#}0.4×0.4

2.6060…{#blank#}4{#/blank#}2.601601……          12×0.65{#blank#}5{#/blank#}1.2×6.5

4.4×2.1={#blank#}1{#/blank#}          0.44×0.21 ={#blank#}2{#/blank#}       0.44×2.1 ={#blank#}3{#/blank#}

4.4×{#blank#}4{#/blank#}=0.924      {#blank#}5{#/blank#}×21=92.4           {#blank#}6{#/blank#}×0.21=9.24