① + + +
② × + ÷
③3.8×9.9+0.38
④(8+ )÷4
⑤6÷ + ÷6
⑥ ÷[( + )× ]
88+8.8= 90÷5= 0.1÷0.2= 0.12×0.8= 0.3²=
÷10= ×0.25= - = + = ×7÷ ×7=