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©2025 数学クラブ http://sugaku.club/
月 日( )
● 次の計算をしなさい
[1C1-00]
(1)
52
×
48
(2)
33
×
27
(3)
81
×
79
(4)
93
×
87
(5)
2
59
(6)
2
82
(7)
2
88
(8)
92
×
88
(9)
77
×
83
(10)
81
×
79
(11)
82
×
78
(12)
2
23
©2025 数学クラブ http://sugaku.club/
月 日( )
【解答例】
(1)
52
×
48
2
2
=
(
50
+
2
)
(
50
−
2
)
=
50
−
2
=
2500
−
4
=
2496
(2)
33
×
27
2
2
=
(
30
+
3
)
(
30
−
3
)
=
30
−
3
=
900
−
9
=
891
(3)
81
×
79
2
2
=
(
80
+
1
)
(
80
−
1
)
=
80
−
1
=
6400
−
1
=
6399
(4)
93
×
87
2
2
=
(
90
+
3
)
(
90
−
3
)
=
90
−
3
=
8100
−
9
=
8091
(5)
2
59
2
2
2
=
(
60
−
1
)
=
60
−
2
×
60
×
1
+
1
=
3600
−
120
+
1
=
3481
(6)
2
82
2
2
2
=
(
80
+
2
)
=
80
+
2
×
80
×
2
+
2
=
6400
+
320
+
4
=
6724
(7)
2
88
2
2
2
=
(
90
−
2
)
=
90
−
2
×
90
×
2
+
2
=
8100
−
360
+
4
=
7744
(8)
92
×
88
2
2
=
(
90
+
2
)
(
90
−
2
)
=
90
−
2
=
8100
−
4
=
8096
(9)
77
×
83
2
2
=
(
80
−
3
)
(
80
+
3
)
=
80
−
3
=
6400
−
9
=
6391
(10)
81
×
79
2
2
=
(
80
+
1
)
(
80
−
1
)
=
80
−
1
=
6400
−
1
=
6399
(11)
82
×
78
2
2
=
(
80
+
2
)
(
80
−
2
)
=
80
−
2
=
6400
−
4
=
6396
(12)
2
23
2
2
2
=
(
20
+
3
)
=
20
+
2
×
20
×
3
+
3
=
400
+
120
+
9
=
529