①19.92+14.4-9.92
②5.17-1.8-3.2
③25×33×4
④6400÷25÷4
⑤265×101-265
⑥6.8+0.85+0.15+2.2
①455÷[(109﹣102)×13]
②156÷12×15+35
③(2400÷48﹣40)×2
④140×[133﹣(154﹣31)]
①0.25×16.2×4
②375+450÷18×25
③35.6- +34.4-
④ × + ÷
⑤[( - )× ]÷
⑥3.5× +5.5×80%+0.8