脱式计算．（能用简便方法的用简便方法）．
3.78﹣1.46+1.54 17.5﹣5.15﹣1.85
4.1×9.9 0.4×（2.5+0.25）
直接写得数
502﹣197= 8.01﹣2.1= 2.5×40= 0.33= 5.2÷0.125÷8=
=
=
=
= 12.5÷（10%÷10）=
直接写出得数．
180÷6= 12.25﹣0.5=
﹣0.5= 202= 23+177%= 2.5×4=
﹣
= 3π=
×
=
+
= 0.6÷
= 2÷1%=
350×0.02= 1﹣25%= 1+15%= 12﹣7.9=
×
=
﹣
=（
﹣）×24= 16×
=
131131÷131=
×
×0= 1÷
﹣÷1= 12.5×0.08=
0.9+99×0.9= 7.8×0.25×4=
﹣
+
= 0.52×100=
×8+8×
=
×21×
= 98﹣0.23﹣0.77=
+÷=
44÷
= 9300÷5÷6= 0÷
= 1997+1998+1999+6=
直接写出得数．
4+4.73= 
÷9= 
×
÷×= 4 
﹣4 
=
375÷1 
= 
×2÷×2= 36+0.4= 5×32×2.5=
1÷0.9= 8×（12+0.5）= 
= 
= 
= 
= 
= 
= 
= 
= 
= 
= 
= 
= 
= 
=
35+0.4= 8×（12+0.5）= 4×0.8×2.5×12.5= 
= 
= 
= ．
直接写出得数．
1﹣0.09=0.45×101= 2÷0.02= 0.25×0.7×0.4=
×
= 5﹣
=
÷
= 2.72+3﹣2.72+3=