①﹣+-
②(﹣)×18×12
③2×1.5+4.5÷0.75
④69×9.9+6.9
49+20= 600﹣340= 1.7+0.2= 1﹣0.3=
+= -= 0.9×0.4= 1.6÷4=
×= ÷= 1.7÷1%= ×1.2=
① ×[0.75﹣( ﹣25%)]÷1.25
②6.37×1.25﹣1 +4.63×125%
③7.09× +0.225×6﹣60%×0.64
④ ×3+ ×25+ ×
⑤
⑥