写出每组数的最大公因数．
12和20
33和11
13和7．
直接写出得数． 
+=
×6= 270÷1= 2÷
=
5﹣0.25= 4.5×100= 2.4+1.6= 7÷0.25=
0×103= 18+15= 12.56÷3.14= 130×7=
1.2÷2%= 0.75×8= 0.33=
×45=
3.14×7= 3.14×0.8=
×
= 64÷0.4=
+
=
﹣
= 1.4÷0.2= 0.9﹣
=
+
= 0.32+3.2=
++2= 2.4×5=×÷×= 1.3×0.8×12.5=
甲数的75%是48，乙数比48少
，乙数比甲数少百分之几？
直接写得数．
3.6+5.4= 650﹣100= 0.008×1000= 70÷0.01=
2.8×0.5= 25÷
= 8.1÷0.03=
+3=
×
=
﹣
= 1÷
=
×
=+
+
=
×0.25=
﹣0.6=1﹣7%=
直接写出下面各题的结果．
56+37= 80﹣16= 31.5+5= 12﹣1.1=
1.2×0.2= 2.87÷0.7=
=
=
30÷50= 25×8=
=
=
12×
1÷
= 0×
=
×2÷×2=
直接写出得数．
684+198= 14.3﹣0.8= 2.5×40= 0.35×99+0.35=
÷6=
1﹣
+
= 3.7×1000= 7×8×（
+
）=
×
=
÷2=
÷
×0=
×4+= 7﹣
=
÷
= 4×
×
=×4÷×4=