9×0.7=6.3

           99×0.77=76.23

         999×0.777=776.223

       9999×0.7777=7776.2223

     {#blank#}1{#/blank#}

     {#blank#}2{#/blank#}

1×9+2＝11，12×9+3＝111，123×9+4＝1111，{#blank#}1{#/blank#}9+{#blank#}2{#/blank#}＝11111．

1.12×9＝10.08

1.123×9＝10.107

1.1234×9＝10.1106

1.12345×9＝{#blank#}1{#/blank#}

……

{#blank#}2{#/blank#}×9＝10.111111101

203×2=406         504×5=2520

306×3=918         803×8=6424

204×4={#blank#}1{#/blank#}       507×{#blank#}2{#/blank#}=1521

509×8={#blank#}3{#/blank#}       408×{#blank#}4{#/blank#}=2448

3×8=24      33×68=2244        333×668=22/2444

3333×6668={#blank#}1{#/blank#}               {#blank#}2{#/blank#}×{#blank#}3{#/blank#}=2222244444。