7.53﹣2.5= 45+215= ×63=
﹣= 24÷= +÷=
47+53= 420÷70= 100﹣28.5= 0.03×8= 234﹣199=
50×80= 2.7÷0.9= += 1÷= ×=
0.25×28= 500×1%= 0.81× = 0.32-0.22=
8×4÷8×4= 1÷3× = 0.8÷0.01= 98÷22=