用简便方法计算．①147+386+853②2485﹣（760+1485）③198÷2×45+45④75×128﹣28×75．
口算80﹣42= 18.2+8= 19﹣0.2= 1.8×0.4=24÷0.6= 21×= ﹣= 100×1%=1.25×8÷1.25×8= ×8+8×=
直接写得数．352+198=+=1.03+0.07=32÷1000=×=0.7：0.25=
直接写出得数．218+682= 0.3÷0.6= 7.8﹣3.6= 0.625×100=÷2= ﹣= ×= （﹣）×24=
直接写出得数．73﹣37= 3.2÷0.4= 2.3+25=×= = =
直接写得数9+= 0.9﹣0.26= 4﹣﹣= ×12=÷7= ×÷×= ﹣= ÷=3.25×4= 0.77+0.33=
= 
﹣
= 100×1%=
×8+8×
=
+
=
×
=
÷2= 
﹣
= 
×
）×24=
×
= 
= 
=
= 0.9﹣0.26= 4﹣
﹣
= 
×12=
÷7= 
×
×
= 
÷
=
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