1+2+3=1○2○3．
4×6-7=4○6○7．
分析：做題時先看這兩題左邊的得數(shù)是多少，再添加運(yùn)算符號，第（1）題左邊1+2+3=6，要使右邊等于6，必須用乘號；第（2）題左邊4×6-7=17，要使右邊也是17，必須添加號．
解答：解：（1）1+2+3=1×2×3；
（2）4×6-7=4+6+7．
點(diǎn)評：此兩題先從等式左邊開始，算出得數(shù)，再去添加符號．
練習(xí)冊系列答案
相關(guān)習(xí)題

科目：小學(xué)數(shù)學(xué) 來源： 題型：

口算．
0.24+6.9= 9.1-7.3= 1.2×6= 7.2+2.8=
31×3= 24×5= 1000÷8= 0.8×0.6=
1.25×4= 300÷50= 480÷0.6= 0.15×9=
3.4×0.7= 2.2×3= 0.2×1.1= 2.1÷0.3=
2
5
+
1
5
=
5
8
-
3
8
=
5
9
+
4
9
=		 1-
1
4
=

查看答案和解析>>

科目：小學(xué)數(shù)學(xué) 來源： 題型：閱讀理解

4.7+2.3= 4.5×2= 6.9-2.5= 7.2×0.8=
6×3.4= 0.62-0.32= 1.4×0.5= 0.75×100=
0.02×0.5= 3.6÷0.3= 6.3÷7= 5.6÷100=
0.75÷0.25= 0.125×8= 4.8÷0.3= 0.96÷2=
0.56÷28= 0.36÷0.4= 0.64÷0.8= 0.72÷3.6=
3.6÷24= 0.8×1.1= 7.2+12.8= 46.7-3.8=
12.8÷4= 5.2÷13= 12.5÷5= 1.64÷41=
10÷20= 24÷15= 8.65×10= 0.35×0.6=
3.08×0.01= 4.95×1000= 6.9×0.1= 0.4×0.5=
2.4÷0.8= 10.8÷9= 9.6÷0.8= 0.108÷2=
4.95÷0.9= 9.65÷0.1= 0.325×100= 2.5×8=
0.56÷0.7= 0.125×4= 3.28×0.1= 3.9÷0.13=
7.2×0.1= 0.01×0.1= 0.25×0.4= 1.6÷0.8=
1÷2.5= 1.25×0.8= 3.2÷0.04= 0÷1.7=
0.22×102= 9.6÷0.8= 5×0.24= 4.5-0.05=
3.9÷0.13 16.5÷0.5= 5×0.12= 24×0.5=
4.8×0.5= 2.8+4.2= 0.84÷2.1= 5÷0.25=
7.8÷0.01= 5.4÷0.6= 3.2÷5= 7×0.62=
0.56÷0.8= 7.4-2.8= 0.18÷0.2= 0.16÷8=
4.5×0.02= 8+7.2= 1.2×30= 0.012×0.2=
7.3×0.3= 9÷6= 3.6÷0.12= 7.8÷0.6=
2÷5= 4.5+5= 0.3÷0.6= 0.96÷0.2=
10.5×0.4= 7.3+0.27= 8×0.125= 0.54÷0.6=
0.61+0.39= 0.56÷28= 10÷20= 4.08÷0.4=
11-9.4= 0.8×0.11= 0.72+12.8= 5.6÷0.01=
2.3×100= 0.75×100= 0.108÷2= 10.8÷9=
0.7÷0.8= 16-5.07= 4.2×0.4= 0.72×6=
12÷0.5= 5.2×0.4= 12.2÷0.2= 5.6÷100=
0.41+3.7= 0.02×0.5= 7.2-0.8= 1.4×0.5=
84÷0.21= 0.75÷0.25= 2.5×16= 0.108÷2=
1.75+32.5= 16-5.07= 5.2÷13= 1.64÷41=
1.02×0.2= 0.26×0.3= 8.4×0.02= 1.29×6=
0.8×0.05= 12.6÷0.03= 8.71÷0.1= 21÷0.21=
0.8×0.13= 0.34÷17= 8.08÷0.4= 0.5×2.2=
1.24÷4= 3.27+0.63= 5.02×0.3= 0.3×0.5=
6.4÷4= 7.2÷1.8= 0.7÷0.35= 0.72÷1.44=
0.48÷0.04= 1.25÷2.5= 5.5+55= 16.8÷8=
0.54+2.2= 3.5-0.05= 2÷0.02= 0.25×40=
1.5×0.6= 0.32÷0.8= 12.25÷0.5= 73.5×0.1=
46.5+52.5= 0.45×102= 1.25×88= 2.64+3.85+1.54=
8×1.25= 5.6÷3.5= 4.2÷0.7÷6= 0.4×8.6×25=
0.27÷0.3= 2.5×101= 0.65×101-0.65= 2.6×7÷2.6×7=

查看答案和解析>>

科目：小學(xué)數(shù)學(xué) 來源： 題型：

觀察已知算式，尋找規(guī)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
．

查看答案和解析>>

科目：小學(xué)數(shù)學(xué) 來源： 題型：

7×5
5
14
=
5
8
÷
2
3
=
1
6
+
2
5
=
2
3
×
3
4
=		 1+
1
2
-0.4=
1
4
+0.75=
1
3
+
2
9
=
6
7
÷9=
1
4
+
1
2
=
5
6
×0.4=		 4÷
8
9
=
1
9
×
1
9
=
（2+
2
5
）×（1+
1
4
）=
2
3
×9=
6
9
+
1
6
=
4÷
1
3
=
1
2
+1
1
3
=		 5-（2+
3
8
）=
4.5÷
1
4
=		 39×
4
13
=		 11×（10+
1
11
）=
11+（3+
2
3
）=
3
5
×
5
6
=		 8×
3
4
=
12-（6+
3
4
）=		 1÷（1+
3
4
）=		 20÷20%=
1÷0.01= 1.12= 9.9÷（1+
4
5
）=
81÷
5
9
=		 1.65-0÷1.65=
2
3
×
4
9
×
1
2
=
5-1.4-1.6= （0.18+0.9）÷9= 8×
3
10
×1.25=
1.25×0.16×8=
5
8
+7.3÷10%=
5
8
+9-0.2=
5.08-0.74-1.26=
1
4
×0.2=		 1-.0375÷
5
8
=
8÷0.5+
1
4
×（1+
1
4
）=		 （
1
12
+
5
6
）×24=		 10（3+
1
7
）÷（3+
1
7
）=
（3+
1
2
+5+
1
3
+2+
1
2
）-（5+
1
3
）=
2
5
+
1
5
÷
2
5
+
1
5
=		 1-
3
10
-
2
5
=
3-（2+
4
9
）+（2+
4
9
）=
3
8
-
3
8
÷3=		 0×（3+
2
9
）+（1+
2
5
）=
1
6
+
1
7
-
1
6
+
1
7
=		 0.125×64×0.125=
5
4
×8+8×
1
4
=
3
8
+
3
4
×16=
5
9
-
5
6
+
4
9
=

查看答案和解析>>

科目：小學(xué)數(shù)學(xué) 來源： 題型：解答題

4.7+2.3=4.5×2=6.9-2.5=7.2×0.8=
6×3.4=0.62-0.32=1.4×0.5=0.75×100=
0.02×0.5=3.6÷0.3=6.3÷7=5.6÷100=
0.75÷0.25=0.125×8=4.8÷0.3=0.96÷2=
0.56÷28=0.36÷0.4=0.64÷0.8=0.72÷3.6=
3.6÷24=0.8×1.1=7.2+12.8=46.7-3.8=
12.8÷4=5.2÷13=12.5÷5=1.64÷41=
10÷20=24÷15=8.65×10=0.35×0.6=
3.08×0.01=4.95×1000=6.9×0.1=0.4×0.5=
2.4÷0.8=10.8÷9=9.6÷0.8=0.108÷2=
4.95÷0.9=9.65÷0.1=0.325×100=2.5×8=
0.56÷0.7=0.125×4=3.28×0.1=3.9÷0.13=
7.2×0.1=0.01×0.1=0.25×0.4=1.6÷0.8=
1÷2.5=1.25×0.8=3.2÷0.04=0÷1.7=
0.22×102=9.6÷0.8=5×0.24=4.5-0.05=
3.9÷0.1316.5÷0.5=5×0.12=24×0.5=
4.8×0.5=2.8+4.2=0.84÷2.1=5÷0.25=
7.8÷0.01=5.4÷0.6=3.2÷5=7×0.62=
0.56÷0.8=7.4-2.8=0.18÷0.2=0.16÷8=
4.5×0.02=8+7.2=1.2×30=0.012×0.2=
7.3×0.3=9÷6=3.6÷0.12=7.8÷0.6=
2÷5=4.5+5=0.3÷0.6=0.96÷0.2=
10.5×0.4=7.3+0.27=8×0.125=0.54÷0.6=
0.61+0.39=0.56÷28=10÷20=4.08÷0.4=
11-9.4=0.8×0.11=0.72+12.8=5.6÷0.01=
2.3×100=0.75×100=0.108÷2=10.8÷9=
0.7÷0.8=16-5.07=4.2×0.4=0.72×6=
12÷0.5=5.2×0.4=12.2÷0.2=5.6÷100=
0.41+3.7=0.02×0.5=7.2-0.8=1.4×0.5=
84÷0.21=0.75÷0.25=2.5×16=0.108÷2=
1.75+32.5=16-5.07=5.2÷13=1.64÷41=
1.02×0.2=0.26×0.3=8.4×0.02=1.29×6=
0.8×0.05=12.6÷0.03=8.71÷0.1=21÷0.21=
0.8×0.13=0.34÷17=8.08÷0.4=0.5×2.2=
1.24÷4=3.27+0.63=5.02×0.3=0.3×0.5=
6.4÷4=7.2÷1.8=0.7÷0.35=0.72÷1.44=
0.48÷0.04=1.25÷2.5=5.5+55=16.8÷8=
0.54+2.2=3.5-0.05=2÷0.02=0.25×40=
1.5×0.6=0.32÷0.8=12.25÷0.5=73.5×0.1=
46.5+52.5=0.45×102=1.25×88=2.64+3.85+1.54=
8×1.25=5.6÷3.5=4.2÷0.7÷6=0.4×8.6×25=
0.27÷0.3=2.5×101=0.65×101-0.65=2.6×7÷2.6×7=

查看答案和解析>>

同步練習(xí)冊答案