怎样简便就怎样算．
①5.5×17.3+2.7×5.5        ②1.25×（6.2﹣5.9）×80        ③1.5×99
④70.3﹣17.48÷7.6          ⑤3.64÷52×23.3                ⑥4.6×（1﹣0.25）+0.75×5.4．