内容正文:
2.8有理数的混合运算
1.计算
1)-20+(-14)-(-18)-13:
(2)(-0.5)-(-31)+275-(+71)
4
27
7
2
(4)(-g-13)×(-24
864
5)2号2.13N2,
2.计算
)(星)×()÷(-哈)×3:
(2)32(2》4(-23(星)2
3.计算:-2+1-18)÷3×号
4.计算:(-1+2)×3+22÷(-4).
5.计算:
(-81)÷星×号÷(-16
2)-42-3×22×)÷(
6.计算:2×(-3)2-4×(-3)-15.
7计第:32(1织
8#第,(-02州号号×(-12)尺
9.计算:-22.(1-0.5)÷1×2-(-3)31.
3
10.计算:
w号8景六
36
(2)-224(-3)2×(-2)-42-1-4.
11,计算:
2
0号÷-2×(-3)-(2)1:
(2)100÷52-14-
号号×2
12.计算:28÷(-2)2-(-4)-3引-52.
13.计算:
1)12(-号)+(-5)×(-2
2
(2)2.1+5)×(-24
326
(3)15(-3+5):
26
((2》2小3(子+(3)(寻2
14.计算:
(1)1-4-(-2)-(-10-4);
2)(-1)10÷2+(-2)3×16--0.5
15.计算:
(1)(+12)-(-7)+(-5)-(+30):
②2+《~唱x(号号是
3》2(-3》乎号是x(-15
16.计算:
(1)-32-(-8)×(-1)5÷(-1)4:
2》12(-号3星-025-受
4
8号量日(
24
17.计算:
1D计第:6~号号42
(2)-32+3×(-1)202.(3+1-3)×(-2)2.
864
18.计算:
0-32÷3+号号)×12-(1)202
2)-2×()+8÷(-2)2
19.计算:
(1)-14+7=[2-(-3)2]:
221-5)(号)218(-3)
20.计算:234-3t(-5)×(-2).
参考答案
1.解:(1)原式=-20-14+18-13
=·29:
(2)原式=-0.5+3.25+2.75-7.5
=-2:
3原武=号气分(吉》号
2772
=5×(11+21.1)
7222
=57
72
(4)原式=
是(-24吉-20+星~2
=9+4-18
=-5:
(5)原式=-4x3.(4-1+1)×12
4
6
=-3-19x12
6
=-3-38
=-41:
(6)原式=·81×4×4.(-27)*27
99
=-16+1
=-15.
2解:D(星)×()÷(-哈)×3
=-31×8x3
429
=-1;
2)32(-24(-2)x(-星-22
=9(-8)-8×(-星)4
=-11+6-4
8
3解:-22+(1-13)÷3×4
=·4+(-12)*3×1
4#(40
=-4+(-1)
=-5.
4.解:原式=1×3+4(-4)
=3-1
=2.
5.解:(1)原式=81×4×4x1
9916
=1:
(2)原式=-16-3x4×(-1)×-3)
6
=-16-12×1x3
64
=-16-3
=哈
6.解:2×(-3)2-4×(-3)-15
=2×9-4×(-3)-15
=18+12+(-15)
=15.
7.解:原式=-
3
41
9
=-1×(-1)-9
3
4
器
8.解:(-0.2)3[(三2)×(-12)]
63
州
125
1+(-10+8)2
12
=1+(-2)2
125
=.14
125
=3124
125
9.解:原式=4-×(2-9)
23
=-4-
11×(-7)
23
=-4-
×3×(-7)
2
=·442
号
10解w号号是*
36
=75-3)x(-36
964
=2×(-36)+5x(-36)
9
6
3×(-36)
=-28+(-30)+27
=-31:
(2)-22+(-3)2×(-
2)-42-4
=-4+9×(-
2
-16-4
=-4+(-6)-4
=-14.
1.解:1)原式=-号(-498)
=-3(-948)
3(-1)
$$= \frac { 3 } { 2 } ;$$
(2)原式
$$= 1 0 0 \div 2 5 - 1 - \left( \frac { 1 } { 2 } \times 1 2 - \frac { 2 } { 3 } \times 1 2 + \frac { 1 } { 4 } \times 1 2 \right)$$
=4-1-(6-8+3)
=4-1-1
=2.
12.解:原式=28-4+4×3-25
=7+12-25
=19-25
=-6.
解
$$\left( 1 \right) | - 2 | = \left( - \frac { 1 } { 2 } \right) + \