1÷0.25= +1= ×24=
+= ﹣= 470×0.02=
10÷= 6×0= 3×﹣×3=
-= += += ÷10= -+=
+= 15÷= ×= ×= ×36-×36=
= = = = =
× × 2 ÷1
÷ ÷ 2 1÷