5.01-1.8= × = 0.24×5= 4÷ + =
+ = 0.91÷0.7= 0.35÷ = 1÷0.1-1×0.1=
①12.7-3.6-5.4
②( + )×15×18
③6× + ÷
④4.2÷[( + )× ]