①48÷8=
②14÷7=
③72÷9=
④40÷5=
①90-28-30=
②100-80-8=
③97-(60-28)=
④62+(55-46)=
⑤78-24+37=
⑥73-(20+35)=
40+25﹣9=
45+19+18=
90﹣60﹣28=