240÷30= 270÷90= 23×300= 400÷80=
70×60= 90+340= 25×40= 4200÷700=
10﹣6.8= ﹣ = 35×1%= 1.25×24= 5× ÷5× =
0.42= 10÷0.02= 5a×7a= 1÷3= 1﹣1÷6=