Exercise1(level b)

(1) Calculation problem:

( 1)23+(-73) (2)(-84)+(-49) (3)7+(-2.04) (4)4.23+(-7.57) (5)(-7/3)+(-7/6) (6)9/4+(-3/2) (7)3.75+(2.25)+5/4 (8)-3.75+(+5/4)+(- 1.5)

(2) Calculate by a simple method:

( 1)(- 17/4)+(- 10/3)+(+ 13/3)+( 1 1/3) (2)(- 1.8)+(+0.2)+(- 1.7)+(0. 1)+(+ 1.8)+(+ 1.4)

(3) It is known that X =+ 17 (3/4), Y =-9 (5/ 1 1) and Z =-2.25.

Find the value of: (-x)+(-y)+z.

(4) if ">" and "0" are used, then a-ba (c) if ba (d) if a.

(2) Fill in the blanks:

(1) zero minus the inverse of a, the result is _ _ _ _ _ _ _ _; ② if a-b >; A, then B is _ _ _ _ _ _ _ _ _ _ _; (3) subtract-π from -3. 14, and the difference should be _ _ _ _ _ _ _ _; (4) The minuend is-12(4/5), with a difference of 4.2, so the minuend should be _ _ _ _ _ _ _ _ _ _ _ _; (5) If B-A

(3) True or false:

(1) When a number subtracts a negative number, the difference is less than the minuend. (2) When a number subtracts a positive number, the difference is less than the minuend. (3) Subtract any number from 0, and the difference is always equal to the reciprocal of this number. (4) If X+(-Y)=Z, then X=Y+Z (5) If 0, b|b|, then a-b >; 0

Exercise 2 (Level B)

(1) calculation: (1) (+1.3)-(+17/7) (2)-(+2/3) (3) | (-7.2)-(-6.

(2) If |a|=4, |b|=2, and |a+b|=a+b, find the value of a-b. 。

(3) If A and B are rational numbers and | a |

(4) If |X- 1|=4, find x and observe the distance between the point representing the number x and the point representing 1 on the number axis.

Exercise 3 (Level A)

(1) Multiple choice questions:

The correct pronunciation of (1) formula -40-28+ 19-24+32 is () (a) minus 40, minus 28, plus 19, minus the sum of 24 and 32, and (b) minus 40 plus/kloc-0. 0, then () (a) At least two of the three numbers are negative (b) Only one of the three numbers is negative (c) At least one of the three numbers is negative (d) Two of the three numbers are positive or two are negative (3) If m

(2) Fill in the blanks:

The general steps of (1) rational number addition and subtraction mixed operation are: (1) _ _ _ _ _ _ _; (2)_________; (3)________ _______; (4) _ _ _ _ _ _ _ _ _ _ _. (2) When b0, (a+b)(a- 1) >; 0, there must be () (A)b with the same number as A (B)a+b with the same number as A-1(c) A > 1 (D)b 1 (6) The product of a rational number and its opposite number () (a) The sign must be positive (b) The sign must be negative (c) It must not be less than zero (d) It must not be greater than zero (7) If | a-1|||.

(2) Fill in the blanks:

The multiplication rule of (1) rational number is: multiply two numbers, Use the same symbol _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _. (4) Calculation: (4a) * (-3b) * (5c) *1/6 = _ _ _ _ _ _ _ _ _ _ _; (5) Error in calculation: (-8) * (1/2-1/4+2) =-4-2+16 =10 is _ _ _ _ _. (6) Calculation: (-1/6) * (-6) * (17) * (-7/10) = [(-16) * (-6)].

(3) True or false:

(1) If the product of two numbers is positive, then both numbers must be positive; (2) If the product of two numbers is negative, then the signs of the two numbers are different; (3) Multiply several rational numbers, and when there are even factors, the product is positive; (4) Multiplying several rational numbers, when the product is negative, there are odd negative factors; (5) The product ratio is greater than each factor.

Exercise (4) (Level B)

(1) Calculation problem:

( 1)(-4)(+6)(-7) (2)(-27)(-25)(-3)(-4) (3)0.00 1*(-0. 1)*( 1. 1) (4)24*(-5/4)*(- 12/ 15)*(-0. / kloc-0/2) (5)(-3/2) (-4/3)(-5/4)(-6/5)(-7/6)(-8/7) (6)(-24/7)( 1 1/8+7/3-3.75)*24

(2) Calculate by a simple method:

( 1) (-7 1/8) * (-23)-23 * (-73/8) (2) (-7/ 15) * (- 18) * (-45/65448)

(4) Given1+2+3+...+31+32+33 =17 * 33, calculate the following formula.

The value of 1-3+2-6+3-9- 12+ ... +3 1-93+32-96+33-99.

Exercise 5 (Level A)

(1) Multiple choice questions:

(1) It is known that A and B are two rational numbers. If their quotient a/b=0, then () (A)a=0 and b≠0 (B)a=0 (C)a=0 or b=0 (D)a=0 or b≠0. -1 and-1; 0 and 0; -2/3 and -3/2, where the reciprocal is () (a) only (b) only (c) only (d) both are (3) If a/|b|(b≠0) is a positive integer, then () |b| is the divisor of a (. B, then there must be () (a) A)A+b & gt；; a(B)a-B & gt； a(C)2a & gt； ab(D)a/b & gt； 1

(2) Fill in the blanks:

(1) When |a|/a= 1, a _ _ _ _ _ _ 0; When |a|/a=- 1, a _ _ _ _ _ _ 0; (fill in > 0, then a _ _ _ _ _ _ 0; (1 1) If ab/c0, then B _ _ _ _ _ _ 0; (12) if a/b >; 0，b/c(-0.3)4 & gt； - 106(B)(-0.3)4 >； - 106 >(-0.2)3(C)- 106 & gt； (-0.2)3 & gt； (-0.3)4(D)(-0.3)4 & gt； (-0.2)3 & gt； -106 (4) If A is a rational number and A2 >；; A, then the value range of A is () (a) A.

(2) Fill in the blanks:

(1)23, 3 is _ _ _ _ _, 2 is _ _ _ _ _ _, and the power is _ _ _ _ _ _ _ _; If 3 is regarded as a power, its cardinal number is _ _ _ _ _ _ _ _,

The index is _ _ _ _ _ _ _ _; (2) According to the meaning of power: (-2)3 stands for _ _ _ _ _ _ _ multiplication; (-3)2v represents _ _ _ _ _ multiplication; -23 means _ _ _ _ _. (3) The rational number whose square equals 36/49 is _ _ _ _ _ _ _; The cubic number equal to -27/64 is _ _ _ _ _ _ _ (4) Write a positive number greater than 10 as a* 10n (n is a positive integer), where the range of a is _ _ _ _ _ _ _ _, where n is an integer.

The number of digits is less than _ _ _ _ _ _, which is called scientific notation; (5) Write down the following numbers by scientific notation: 4000 = _ _ _ _ _ _ _ _ _ _ _ _; 950000=________________; earth

The mass is about 49800 ... 0g (28 bits), which can be recorded as _ _ _ _ _ _ _ _; (6) What are the numbers recorded by scientific notation, namely105 = _ _ _ _ _ _ _ _ _ _ _; 2* 105=______________; 9.7 *107 = _ _ _ _ _ _ 9.756 *103 = _ _ _ _ _ (7) The following numbers are natural numbers. 7* 106 is 3.78* 107 is _ _ _ _ digits; 10 10 is _ _ _ _ _ digits; (8) If rational number m 0, B0 (b) a-| b | > 0 (c) A2+B3 > 0 (d) A <; 0 (6) The minimum value of algebraic expression (a+2)2+5 is () (a) A = 0 (b) A = 2 (c) A =-2 (d) A0 (b) B-A >; 0 (c) A and B are reciprocal; (D)-ab (C)a

(5) The approximate value 1.20 obtained by rounding method represents the range of the exact number a ().

(A) 1. 195≤A & lt； 1.205(B) 1. 15≤a & lt； 1. 18(C) 1. 10≤a & lt； 1.30(D) 1.200≤a & lt； 1.205 (6) The following statements are correct: (a) The accuracy of similarity number 3.80 is the same as that of similarity number 38; (b) The number of significant digits of similarity number 38.0 is the same as that of similarity number 38. (c)3. 14 16 has three significant digits 3, 1 4 after being accurate to the percentile; (d) Write 123* 102 as 1.23* 104 with four significant digits.

(2) Fill in the blanks:

(1) Write the precision and significant figures of the following rounded approximations: (1) Approximate number 85 is accurate to _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ (3) The divisor of 5.2 million is accurate to _ _ _ _ _ _ _ _, and the effective number is _ _ _ _ _ _ _ _; (4) The approximate value of 0.20 is accurate to _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _.

The divisor 2.7 183 is accurate to _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _.

(3) True or false:

(1) The approximate value of 25.0 is exactly a dash, and the significant digits are 2,5; (2) Similarity number 4000 is as accurate as similarity number 4000; (3) The divisor 4000 is as accurate as the divisor 4 * 10 3; (4) The approximate value of 9.949 accurate to 0.0 1 is 9.95.

Exercise 8 (Level B)

(1) Use rounding method to approximate the following figures (three significant figures are required): (1) 37.27 (2) 810.9 (3) 0.0045078 (4) 3.079.

(2) Use rounding method to approximate the following numbers (accurate to thousands): (1) 37890.6 (2) 213612.4 (3)1906.57.

(3) Calculation (the result is reserved with two significant figures): (1) 3.14 * 3.42 (2) 972 * 3.14 *14.

Exercise 9

(a) look-up table evaluation:

( 1)7.042 (2)2.482 (3)9.52 (4)2.00 12 (5) 123.42 (6)0. 12342 (7) 1.283 (8)3.4683 (9)(-0.5398)3 ( 10)53.733

(2) Given that 2.4682=6.90 1, we can find the values of 24.682 and 0.024682 without looking up the table.

(3) 5.2633= 145.7 is known, so we don't look it up.

( 1)0.52633 (2)0.05263 (3)52.632 (4)52633

(4) Given 21.762 2 = 473.5, what is the approximate value of 0.002 1762 with three significant digits?

(5) Look-up table calculation: the surface area of a ball with a radius of 77cm (the area of the ball =4π*r2).

The second copy

Math Test of Junior One (6)

(Chapter 1 Rational Number 200 1, 10, 18) Proposer: Sun Score.

I. Multiple-choice questions: (3 points for each question, 30 points for * * *)

1.|-5 | equals ........................................... ()

(A)-5 (B)5 (C) 5 (D)0.2

2. The number represented by the origin and the point to the right of the origin on the number axis is ....................... ().

(a) Positive number (b) Negative number (c) Non-positive number (d) Non-negative number

3. The algebraic expression "the difference between the products of two numbers B and M" is ..................... ().

(A) (B) (C) (D)

4. The number whose reciprocal equals itself is ................................... ().

(A) 1 (B)2 (C)3 (d) countless.

5. Of the six numbers (n is a positive integer), the number of negative numbers is ..................................................... ().

1 (B)2 (C)3 (D)4。

6. If point A and point B on the number axis correspond to rational numbers A and B respectively, the following relationship is correct ().

(A)a | b |, then a+b 0. (Fill in ">" or "=" or "

17. Fill in the appropriate item on the horizontal line in brackets: 2x-(3a-4b+c) = (2x-3a)- ().

18. Observe the following formula and you will find the law: ; ; ; ..... Please use the same letter to represent the number, and use the equation to represent the law in the above formula.

Three. Calculation (write down the calculation process): (7 points for each question, ***28 points)

19.20.

2 1.(n is a positive integer)

22.

Fourth, if. (1) Find the values of a and b; (4 points for this question)

(2) the value. (6 points for this question)

The third copy

Math Test of Junior One (6)

(Chapter 1 Rational Number 200 1, 10, 18) Presenter: Sun.

Class name score

I. Multiple-choice questions: (3 points for each question, 30 points for * * *)

1.|-5 | equals ........................................ ()

(A)-5 (B)5 (C) 5 (D)0.2

2. The number represented by the origin and the point to the right of the origin on the number axis is ..................... ().

(a) Positive number (b) Negative number (c) Non-positive number (d) Non-negative number

3. The algebraic expression "the difference between the products of b and m" is ................. ().

(A) (B) (C) (D)

4.-12+1-8+39 = (-12-8)+(11+39) is the application of ().

A, additive commutative law b, additive associative law c, additive commutative law and associative law d, multiplicative distributive law.

5. Rewrite 6-(+3)-(-7)+(-2), omit the plus sign, and the total should be ().

a、6-3+7-2 B、6-3-7-2 C、6-3+7-2 D、6+3-7-2

6. If |x|=3 and |y|=7, the value of x-y is ().

A, 4 B, 10c, -4 or-10d, 4, 10.

7. If a× b < 0, there must be ().

A, a > 0, b < 0 b, a < 0, b > 0 c, a and b are the same number, and d, a and b are different numbers.

8. If the sum of two rational numbers is positive and the product is negative, then these two rational numbers ().

A, both are positive numbers. B, the number with the largest absolute value is positive and the other is negative.

C, all negative numbers D, the number with the largest absolute value is negative, and the other is positive.

9. Stationery store, bookstore and toy store are located in an east-west street in turn. The stationery store is 20 meters west of the bookstore, and the toy store is 20 meters east of the bookstore 100 meters. Xiaoming walks 40 meters east from the bookstore, and then walks -60 meters east. At this time, Xiao Ming's position is ().

A, stationery store B, toy store C, stationery store D is 40 meters west, and toy store is -60 meters east.

10. What is the known rational number and its position on the number axis?

As shown in the figure, when 1a > 0, ②-b < 0, ③ a-b > 0,

(4) Among the four relationships of A+B > 0, the correct one is ().

a，4 B，3 C，2 D， 1

2. True or false questions: (For the right picture "+",the wrong picture "○", each question 1, and ***6).

1 1.0.3 is neither an integer nor a fraction, so it is not a rational number. ( )

12. The absolute value of rational number is equal to the reciprocal of this number, which is negative. ( )

13. The increase in income is recorded as +5 yuan in 5 yuan, and the decrease in expenditure is recorded as -5 yuan in 5 yuan. ( )

14. If a is rational, -a must be negative. ( )

15. If you subtract a rational number from zero, you still get this number. ( )

16. Multiply several rational numbers. If the number of negative factors is odd, the product is negative. ( )

Three. Fill in the blanks: (3 points for each question, *** 18 points)

17. Fill in the appropriate items in brackets to make the equation hold: A+B-C+D = A+B- ().

18. Comparative size: │-│-│. (fill in ">" or "

19. As shown in the figure, if the distance between any two adjacent points in the points marked on the number axis is equal, then the value of a =.

?

20. One addend is 0. 1, and the sum is -27.9, and the other addend is.

The sum of 2 1 -9, +6 and -3 are less than the sum of their absolute values.

22. Equation × [(-5)+(- 13)] = According to the algorithm of is.

4. Fill in the results directly in the following lines: (2 points for each question, *** 12 points)

23.-2+3= ; 24.-27+(-5 1)= ; 25.- 18-34= ;

26.-24-(- 17)= ; 27.- 14×5= ; 28.- 18×(-2)= 。

Verb (abbreviation of verb) calculation (write down the calculation process): (6 points for each question on 29 and 30, 7 points for each question on 3 1 32, ***26 points)

29.(-6)-(-7)+(-5)-(+9) 30.

3 1.32.(-5)×(-3 )- 15× 1 +〔 -( )×24〕

6. The following table lists the time differences between several foreign cities and Beijing (numbers with a plus sign indicate that the same time is several hours earlier than Beijing time).

(1) If the current Beijing time is 7: 00, what is the current new york time?

Xiaohua wants to call her grandfather in Paris now. Do you think it's appropriate? (4 points for each small question)