问题 解答题
先观察,再根据规律,把算式填完整.
(1)22-12=3,32-22=5,72-62=13,222-______=______,______-782=______;
(2)
1
2
-
1
3
=
3-2
2×3
=
1
6
1
4
-
1
7
=
7-4
4×7
=______,
1
5
-
1
9
=______=______.
答案

(1)222-212=43,792-782=157;

(2)

1
4
-
1
7
=
7-4
4×7
=
3
28
1
5
-
1
9
=
9-5
5×9
=
4
45

故答案为:212,43,792,157,

3
28
9-5
5×9
4
45

解答题
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