①7.4﹣6.62+20.6﹣13.38
②×+×
③(-+)÷
④2×0.8×12.5×50%
⑤÷(÷+)
⑥×[1÷(+)]
①
②
③0.79×99+0.79
④3.8×97+0.38×30
⑤
⑥(﹣)×9×12
①75.6×27﹣170×7.56
③
④