直接写出得数．
400×5= 0×39= 32÷4=
= 405×2≈
72÷8= 12×3= 420+170=
= 89×7≈
90﹣43= 80÷9= 3000×2=1﹣
= 392×5≈
68÷7= 21×5= 61﹣16=
= 58×6≈
直接写得数
40+35= 108﹣82= 10×0= 72÷8=
700×6= 10×4= 35÷6= 3×8+4=
21×5≈ 48×7≈ 199×2≈ 108×3≈
+
=
+
= 1﹣
=
=．
直接写得数．
26+29= 22×4= 44+17= 90÷3=
80﹣45= 1300﹣500= 120×3= 64﹣18=
88÷2= 500×6= 1400﹣700= 300×7=
+
=
﹣
=
+=
﹣
=
直接写出得数．
48+35= 7.5﹣5=
×
=
﹣
=﹣
=
÷
=
﹣
+
=
÷2÷= 25×26×4=
142+54= 320+145= 640﹣238= 0×18= 30×4=
50×6=
+
=
﹣
=
+
= 1﹣
=