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1×1-2×2+3×3-4×4+5×5-6×6+…-100×100+101×101.
1×1-2×2+3×3-4×4+5×5-6×6+…-100×100+101×101,
=1012-1002+…+32-22+1,
=(101-100)×(101+100)+…+(3-2)×(3+2)+1,
=101+100+99+98+…+2+1,
=(101+1)×101÷2,
=5151.
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科目:小学数学 来源: 题型:

3.5×0.4= 2.5×0.4= 2.3×0.2= 2.1÷0.3=
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4.79+15.81= 0.3÷0.03= 0.2×0.1= 3.6+6.4=
0.56÷0.28= 1.2×0.3= 6.7-5.6= 7.25÷0.5=
4.2÷0.21= 4.3×0= 0.15÷0.5= 3.5×4=
5.32-5.3= 1.25×3.4×8= 9.6÷3.2= 3.6+2.4=
4.3-2.7+5.7= 7.2-5.6= 1.8÷0.9= 8.2×0.5=
5.6÷0.4= 8.5÷5= 5.6×0.5= 9.8÷0.2=
3.56×0.2= 3.4+1.5+4.6= 3.4×0.04= 6.12+3.48=
6÷0.12= 7.6÷4= 3.4×0.5= 5.2-3.2-1.8=
6-3.8= 7.5÷3= 3.5+5.4= 3×2.5=
3.5+6.5= 7-6.23= 8÷0.4= 0.25×2.5=
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科目:小学数学 来源: 题型:

3×1.5= 2.5×4= 0÷0.9= 4÷0.2=
0.56÷0.7= 0.24×5= 0.2×5= 2.1-0.87=
3.54-3.5= 3.4-1.5= 12÷0.6= 8×0.125=
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0.2×0.3= 1.2+0.56= 3-1.7= 1÷0.25=
78÷1.3= 15÷0.3= 2.1+1.49= 6.24-1.5=
1.2×0.3= 6.3÷6.3= 1.6×0.2= 3.7-1.2=
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3.2-2= 0.51÷17= 5.3÷0.01= 1.03×3=
2.8+12= 3.5×2= 2.2×0.1= 1-0.25=
0.62-0.32= 6.3÷0.21= 1.7×10= 0.12×3=
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0.25×8= 0.89÷8.9= 17.8+2.2= 0.8÷0.2=
5.79÷0.1= 0.35+0.65= 8.9-0.9= 9.2-9.2=
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科目:小学数学 来源: 题型:阅读理解

1.
(1)438+203 (2)256+199 (3)416-302 (4)325-198
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5
+
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(30)(
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3
-
1
6
+
1
4
)×12
(31)(
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3
+
1
8
-
1
24
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1
24
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3
+
1
8
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24
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3
+
1
8
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24
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5
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1
4
(35)3.3×
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4
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7
10
+75%
(36)2
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2
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3
5
(37)9.56×180-95.6×8
(38)4.8×37+47×6.3 (39)9.5×8.8+0.12×95 (40)
19
20
×21
(41)
7
30
×33
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2
45
÷
1
46
(43)
2
45
÷
1
48
(44)
2
45
÷42
(45)6×0.75+5×
3
4
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3
7
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1
2
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3
7
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1
2
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(54)84-(54+16) (55)9999×7778+3333×6666 (56)3.6×31.4+43.9×6.4 (57)(
3
4
+
5
6
)×
12
5
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7
9
×
13
14
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9
÷
14
13
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23
20
-
1
3
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2
3
(60)
6
11
×
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8
-
6
8
×
5
11
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2
×
1
4
÷
1
2
×
1
4
(62)
25
17
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1
3
×
9
8
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5
8
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8
9
×[
3
7
÷(
2
3
+
1
7
)]
(64)(0.9+5)×3+2.3 (65)56×
1
57
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3
4
+
1
4
÷
3
4
+
1
4
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3
4
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1
4
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3
4
+
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4
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15
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30
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15
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30
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1
15
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9
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4
9
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8
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11
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2
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25
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8
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4
7
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13
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21
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3
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3
7
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3
28
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4
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1
6
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13
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40
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1
7
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9
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6
7
+
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8
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8
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24
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13
16
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16
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3
11
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27
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1
36
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9
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11
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7
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11
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4
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×(10+
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15
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24
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5
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×
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5
8
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÷
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13
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8
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8
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12
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(121)560÷16÷5
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11
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5
12
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12
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12
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2
15
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×
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7
16
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16
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5
6
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3
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12
13
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科目:小学数学 来源: 题型:

观察已知算式,寻找规律填空.
(1)1=1×2÷2
1+2=2×3÷2
1+2+3=3×4÷2
1+2+3+4=4×
5
5
÷2
1+2+3+4+5=
5
5
×
6
6
÷
2
2

1+2+3+4+5+6+7=
7
7
×
8÷2
8÷2

1+2+3+…+n=
n
n
×
(n+1)÷2
(n+1)÷2

(2)1×2=1×2×3÷3
1×2+2×3=2×3×4÷3
1×2+2×3+3×4=3×4×5÷
3
3

1×2+2×3+3×4+4×5=4×5×
6
6
÷
3
3

1×2+2×3+3×4+4×5+5×6=
5
5
×
6
6
×
7÷3
7÷3

1×2+2×3+3×4+…+n×(n+1)=
n
n
×
(n+1)
(n+1)
×
(n+2)
(n+2)
÷
3
3

(3)1×2×3=1×2×3×4÷4
1×2×3+2×3×4=2×3×4×5÷4
1×2×3+2×3×4+3×4×5=3×4×5×
6
6
÷4
1×2×3+2×3×4+3×4×5+4×5×6=
4
4
×
5
5
×
6
6
×
7
7
÷
4
4

1×2×3+2×3×4+3×4×5+4×5×6+5×6×7=
5
5
×
6
6
×
7
7
×
8
8
÷
4
4

1×2×3+2×3×4+…+n×(n+1)×(n+2)=
n
n
×
(n+1)
(n+1)
×
(n+2)
(n+2)
×
(n+3)
(n+3)
÷
4
4

猜一猜:
1×2×3×4+2×3×4×5+3×4×5×6=
3×4×5×6×7÷5
3×4×5×6×7÷5

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科目:小学数学 来源: 题型:

按从大到小的顺序写出5个正数和5个负数.
正数:
5
5
4
4
3
3
2
2
1
1

负数:
-1
-1
-2
-2
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-4
-4
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