{#blank#}1{#/blank#}×{#blank#}2{#/blank#}＝ 12.1  

{#blank#}3{#/blank#}×{#blank#}4{#/blank#}＝ 1.21  

{#blank#}5{#/blank#}×{#blank#}6{#/blank#}＝ 0.121  

例：0.36=4×0.09   0.36=1.2×0.3   0.36=0.18×2

8.4

5.96×1.01{#blank#}1{#/blank#}3.96            3.6÷0.24{#blank#}2{#/blank#}3.6              3.45÷1.2{#blank#}3{#/blank#}3.45÷1.5

6.7×0.98{#blank#}4{#/blank#}0.98×6.7        2.5×0.9{#blank#}5{#/blank#}2.5÷0.9       3.76×0.8{#blank#}6{#/blank#}3.76÷0.8

720.5=36    720.5=144     721.5=48      721.5=108