12÷3+7= (76-36) ÷8= 45+21÷3= 18÷9-2=
35-21+24= 25- 5×3= 18÷(9- 3)= 4-1×3 =
①70-36+24
②8×9-25
③(66-26)÷8
④20+63÷9