(2)8+(-6.45)-42+9 1
(3)(-20)+(+3)-(-5)-7
(4)(-8)+ 10+2-57
(5)5.9+8.4-(-78)+(-3.8)
(6)4.8-(-69)+6.5-(-77)
(7)(-8)-6 1-(3 1)+(-2.9)
(8)9.3+(-7.2)-(+3)+5.2
(9)(-5)+ 13-(-5.8)-(-54)
( 10)(+ 13)-9.6+(-20)
[-|98|+76+(-87)]*23[56+(-75)-(7)]-(8+4+3)
5+2 1*8/2-6-59
68/2 1-8- 1 1*8+6 1
-2/9-7/9-56
4.6-(-3/4+ 1.6-4-3/4)
1/2+3+5/6-7/ 12
[2/3-4- 1/4*(-0.4)]/ 1/3+2
22+(-4)+(-2)+4*3
-2*8-8* 1/2+8/ 1/8
(2/3+ 1/2)/(- 1/ 12)*(- 12)
(-28)/(-6+4)+(- 1)
2/(-2)+0/7-(-8)*(-2)
( 1/4-5/6+ 1/3+2/3)/ 1/2
18-6/(-3)*(-2)
(5+3/8*8/30/(-2)-3
(-84)/2*(-3)/(-6)
1/2*(-4/ 15)/2/3
-3x+2y-5x-7y
Mixed operation of rational number addition and subtraction
1. Multiple choice question:
(1) Write -2-(+3)-(-5)+(-4)+(+3) in the form of omitting brackets, and the correct one is ().
A.-2-3-5-4+3 B.-2+3+5-4+3
C.-2-3+5-4+3 D.-2-3-5+4+3
(2) The result of calculating (-5)-(+3)+(-9)-(-7)+ is correct ().
A.- 10 B.-9 C.8 D.-23
(3) The algebraic sum of-7,-12 and +2 is less than the sum of their absolute values ()
A.-38 B- 4 c . 4d . 38
(4) If +(b+3)2=0, the value of b-a- is ().
A.-4 B.-2 C.- 1 D. 1
(5) The following statement is true ()
A. the subtraction of two negative numbers is equal to the subtraction of absolute values.
B the difference between two negative numbers must be greater than zero.
C. A positive number minus a negative number is actually the algebraic sum of two positive numbers.
D. negative negative positive equals the absolute value of negative plus positive.
(6) Equation -3-5 cannot be read as ()
The difference between A.-3 and 5. The sum of b. 3 and -5.
Difference between c-3 and -5d-3 minus 5
2. Fill in the blanks: (4 ′× 4 =16 ′)
( 1)-4+7-9=- - + ;
(2)6- 1 1+4+2=- + - + ;
(3)(-5)+(+8)-(+2)-(-3)= + - + ;
(4)5-(-3 )-(+7)-2 =5+ - - + - .
3. Write the following form in the form of sum, without brackets, and say two pronunciation ways: (8 ′× 2 =16 ′)
( 1)(-2 1)+(+ 16)-(- 13)-(+7)+(-6);
(2)-2 -(- )+(-0.5)+(+2)-(+ )-2.
4. Calculation problem (6 ′× 4 = 24 ′)
( 1)- 1+2-3+4-5+6-7;
(2)-50-28+(-24)-(-22);
(3)- 19.8-(-20.3)-(+20.2)- 10.8;
(4)0.25- +(- 1 )-(+3 ).
5. When x =-3.7, y =- 1.8 and z =- 1.5, find the value of the following algebraic expression (5 ′× 4 = 20 ′).
( 1)x+y-z; (2)-x-y+z; (3)-x+y+z; (4)x-y-z。
( 1) (-7)-(+5)+(+3)-(-9)=-7 5 3 9;
(2)-(+2 )-(- 1 )-(+3 )+(- )
=( 2 )+( 1 )+( 3 )+( );
(3)- 14 5 (-3)=- 12;
(4)- 12 (-7) (-5) (-6)=- 16;
(5)b-a-(+c)+(-d)= a b c d;
2. When x=, y=- and z=- respectively, find the values of the following algebraic expressions;
( 1)x-(-y)+(-z); (2)x+(-y)-(+z);
(3)-(x)-y+z; (4)-x-(-y)+z。
3. Verify the equations of the following three groups of numbers:
Is it true that a-(b-c+d)=a-b+c-d?
( 1)a=-2,b=- 1,c=3,d = 5;
(2)a=23,b=-8,c=- 1,d= 1。
Computational problem
( 1)- 1-23.33-(+76.76);
(2) 1-2*2*2*2;
(3)(-6-24.3)-(- 12+9. 1)+(0-2. 1);
(4)- 1+8-7
A water conservancy survey team swam 5 kilometers on the first day, 5 kilometers on the second day, 4 kilometers on the third day and 4.5 kilometers on the fourth day. Where is the survey team at this time? How many kilometers apart?
Reference answer:
1.( 1)C; (2)B; (3)D; (4) a; (5)C; (6)C 2。 ( 1)4,(-7),(-9) (2)(-6),(- 1 1),(-4),2; (3)-5,8,2,3; (4)3,7,2;
3. Omit 4. ( 1)-4; (2)-80; (3)-30.5 (4)-5
5.( 1)-4; (2)4; (3)0.4; (4)-0.4.
1.( 1)-,+,+; (2)-,+,-,-; (3)+,+; (4)-,+,+; (5)-,+,-,-.
2.( 1) (2) (3) (4)-
3.( 1) and (2) both hold.
4.( 1)-
(2)
(3)-29.5
(4)- 1 Question (4) Note that the numbers with the same sign and the opposite sign should be combined separately.
1. Upstream 1 km
Respondent: juli Andy- Chief Operating Officer level1210-413: 34.
Add:
5+(-2)
(-7)+9
(-4)+7+(- 15)
9+7+(-3)
2+(-5)
18+(-9)
29+(- 17)
(-28)+ 18
9+8+(-25)
(-26)+ 17
19+(-3)
(-32)+25
25+(-2 1)
5+ 19+(-36)
(-80)+60
128+(-72)+ 12
19+(- 17)
(-9)+7+(-23)
25+(- 19)
290+(-78)
(After 20 passes)
I hope you do well in the exam.
Practice more.