问题 解答题
直接写出得数.
2
9
×6=
3
4
=
3
4
×10=
4
9
×
3
8
=
4
7
×4=
4
7
×
3
4
=
2
3
+
3
4
=
0.25×
2
5
=
b
a
×
c
b
=
b
a
=
1
a
-
1
b
=
1
a
+
1
b
=
2
9
×
3
2
×3=
2
9
×
5
12
×
6
5
=
答案

2
9
×6=
4
3
3
4
=0,
3
4
×10=
15
2
4
9
×
3
8
=
1
6
4
7
×4=
16
7
4
7
×
3
4
=
3
7
2
3
+
3
4
=
17
12
0.25×
2
5
=0.1,
b
a
×
c
b
=
c
a
b
a
=b,
1
a
-
1
b
=
b-a
ab
1
a
+
1
b
=
b+a
ab
2
9
×
3
2
×3=1,
2
9
×
5
12
×
6
5
=
1
9

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