170﹣90=
0.46+0.4=
0.56÷0.8=
× =
6﹣4.92=
25×0.7×4=
+0.5=
3- =
6.3÷0.21=
1﹣1÷ =
(0.6- )×16=
1.85﹣+= 1÷×= +0.375=
2.4﹣= (+)×2.4= 5÷×5÷=
10×45%= 1.25×8= 40×(1﹣20%)=
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