x-20%x=4.8
x=
0.756÷18=
44.8×32=
7.65+0.87.65 10.23×0.9910.23 4.58÷2.34.58
9.8×59.8÷0.2 b×0.1b+0.1(b≠0) 0.25×0.92.5
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②