0.36x0.36 0.75x0.54 0.24x0.370.81÷0.9 0.63÷0.7 0.64÷0.9
0.8×0.2 0.4×0.4 0.1×1.60.9÷0.3 0.3÷0.1 0.6÷0.2
18.9×2.1 27.8×21.3 57.5×10.2 20.5÷20.5 30.5÷10.5 50.5÷37.5
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