100-59= 960÷32= 530+70= 780×0= 25×4=
29+81= 230-80= 0÷999= 12×30= 125×8=
①38+56÷7×4
②940×[128-(154-31)]
③209+102÷(52-35)
④450+390÷130-123
①528-53-47
②78×99
③17×23-23×7
④3200÷4÷25