①52+420÷7
②732 ÷(283-280)
③42+53 ×2
④9×(34+66)
⑤536+81÷9
⑥570-280÷4
①54×98
②(+﹣)×24
③4.86×[1÷(2.1﹣2.09)]
④8﹣