［文字サイズの変更］
▼
▲
©2026 数学クラブ http://sugaku.club/
月 日（ ）
● 次の計算をしなさい
[1C1-00]
(1)
2
47
(2)
17
×
23
(3)
2
39
(4)
31
×
29
(5)
2
21
(6)
92
×
88
(7)
18
×
22
(8)
33
×
27
(9)
102
×
98
(10)
47
×
53
(11)
2
42
(12)
49
×
51
©2026 数学クラブ http://sugaku.club/
月 日（ ）
【解答例】
(1)
2
47
2
2
2
=
(
50
−
3
)
=
50
−
2
×
50
×
3
＋
3
=
2500
−
300
＋
9
=
2209
(2)
17
×
23
2
2
=
(
20
−
3
)
(
20
＋
3
)
=
20
−
3
=
400
−
9
=
391
(3)
2
39
2
2
2
=
(
40
−
1
)
=
40
−
2
×
40
×
1
＋
1
=
1600
−
80
＋
1
=
1521
(4)
31
×
29
2
2
=
(
30
＋
1
)
(
30
−
1
)
=
30
−
1
=
900
−
1
=
899
(5)
2
21
2
2
2
=
(
20
＋
1
)
=
20
＋
2
×
20
×
1
＋
1
=
400
＋
40
＋
1
=
441
(6)
92
×
88
2
2
=
(
90
＋
2
)
(
90
−
2
)
=
90
−
2
=
8100
−
4
=
8096
(7)
18
×
22
2
2
=
(
20
−
2
)
(
20
＋
2
)
=
20
−
2
=
400
−
4
=
396
(8)
33
×
27
2
2
=
(
30
＋
3
)
(
30
−
3
)
=
30
−
3
=
900
−
9
=
891
(9)
102
×
98
2
2
=
(
100
＋
2
)
(
100
−
2
)
=
100
−
2
=
10000
−
4
=
9996
(10)
47
×
53
2
2
=
(
50
−
3
)
(
50
＋
3
)
=
50
−
3
=
2500
−
9
=
2491
(11)
2
42
2
2
2
=
(
40
＋
2
)
=
40
＋
2
×
40
×
2
＋
2
=
1600
＋
160
＋
4
=
1764
(12)
49
×
51
2
2
=
(
50
−
1
)
(
50
＋
1
)
=
50
−
1
=
2500
−
1
=
2499