⑴;
⑵
⑶;
⑷
7.28﹣(1.28+0.25) ÷[×(0.5+)]
23× 3.7×+1.3÷
①
②
③
④
①÷×
②×3.2+6.8÷
③105×(+)
④﹣+﹣
⑤6.4÷[(3﹣1.4)×]