按要求写数．（1）写出3个约等于4.9并且比4.9小的两位小数．（2）写出3个约等于7.0并且比7.0大的两位小数．
直接写得数.+=+= 1﹣=﹣=﹣=﹣=++1=++=+=+= 1﹣﹣=+﹣=
口算.+=﹣=+﹣= 3+=+= 1﹣﹣=++= 4﹣=
计算：．
= ．
+
=
+
= 1﹣
=
﹣
=
﹣
﹣
=
+
+1=
+
+
=
+
=
+
= 1﹣
﹣
=
+
﹣
=
+
﹣
=
+
﹣
= 3+
=
+
= 1﹣
﹣
=
+
+
= 4﹣
=
．
= ．
= ．
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