1+3+5+7+9+11+13+15=

1+3+5+7+9+11+13+15=

sixty-four

(5/1+7/1+9/1+11/1)*(7/1+9/1+11/1+13/1)-(5/1+7/1+9/1+11/1+13/1)*(7/1+9/1+11/1)

Let u = 5 / 1 + 7 / 1 + 9 / 1 + 11 / 1, v = 7 / 1 + 9 / 1 + 11 / 1,
The original formula = u (V + 13 / 1) - (U + 13 / 1) v = 13 / 1 (U-V) = 13 / 1 * 5 / 1 = 65 / 1

1-3+5-7+9-11+13+…… What's the symbol before 99? It's like a sequence?

The positive number term is 15 9 13
Negative terms are - 3 - 7 - 11
According to the formula of arithmetic sequence, the positive number term is an = 4n-3 and the negative number term is an = 4N-1
When 4N-1 = - 99, n is an integer, so the sign before 99 is-

Rational number test in grade one of junior high school
I'm talking about rational numbers
Everybody help
And some practical problems
Would you?
Foundation, calculation and filling in the blanks

Chapter one rational numbers
1、 Multiple choice questions
1. The correct number of the following statements is ()
① A rational number is either an integer or a fraction
③ An integer is either positive or negative. A fraction is either positive or negative
A 1 B 2 C 3 D 4
2. A and B are rational numbers. The positions of their corresponding points on the number axis are shown in the following figure:
Put a, - A, B, - B in the order from small to large ()
A -b＜-a＜a＜b B -a＜-b＜a＜b C -b＜a＜-a＜b D -b＜b＜-a＜a
3. The following statement is correct ()
① 0 is the rational number with the smallest absolute value. 2. The number whose opposite number is greater than itself is negative
③ The numbers on both sides of the origin on the number axis are opposite to each other
A ①② B ①③ C ①②③ D ①②③④
4. The following operations are correct ()
A B －7－2×5=－9×5=－45
C 3÷ D －(-3)2=-9
5. If a + B < 0, AB < 0, then ()
A a＞0,b＞0 B a＜0,b＜0
C, a and B are positive and negative, and the absolute value of positive number is greater than that of negative number
D A and B are positive and negative, and the absolute value of negative number is greater than that of positive number
6. The words of (25 ± 0.1) kg, (25 ± 0.2) kg and (25 ± 0.3) kg are marked on the three brands of flour bags sold by a grain store. Take out any two bags from them, and their mass difference is the most ()
A 0.8kg B 0.6kg C 0.5kg D 0.4kg
7. For a 1 m long stick, cut off the first time, cut off the rest of the stick in the second time, and cut down in this way, the length of the stick left after the fifth time is ()
A ( )5m B [1－( )5]m C ( )5m D [1－( )5]m
8. If ab ≠ 0, then the value of can't be ()
A 0 B 1 C 2 D -2
2、 Fill in the blanks
9. The sum of all integers larger than and smaller than is
10. If so, 2A must be
11. If 0 ＜ a ＜ 1, then the size relation of a, A2, is
12. The time difference between Toronto and Beijing is – 12 hours (positive number means the time earlier than Beijing time at the same time). If Beijing time is 14:00 on October 1, then Toronto time is
Shanghai Pudong maglev railway has a total length of 30km and a one-way running time of about 8min. The average speed of maglev train is about M / min in scientific notation
14. If a * b = 5A + 2b-1, the value of (- 4) * 6 is
15. Given that = 3, = 2, and ab < 0, then A-B =
16. Given a = 25, B = - 3, then the last digit of A99 + B100 is
3、 Calculation problem
17． 18.8－2×32－(-2×3)2
nineteen
20.[-38-(-1)7+(-3)8]×[- 53]
21.–12 × (-3)2－(- )2003×(-2)2002÷
22.–16－(0.5- )÷ ×[-2-(-3)3]－∣ －0.52∣
4、 Answer the question
23. Known 1 + 2 + 3 + +31 + 32 + 33 = = 17 × 33, find 1-3 + 2-6 + 3-9 + 4-12 + +31-93 + 32-96 + 33-99
24. In numbers 1,2,3 Add "+" or "-" before 50 and find the sum of them. What is the minimum nonnegative number of the result? Please list the solution of the formula
25. A maintenance team starts from place a and repairs the line on the east-west road. If it is specified that driving eastward is positive and driving westward is negative, the record of driving seven times a day is as follows. (unit: km)
The first time, the second time, the third time, the fourth time, the fifth time, the sixth time and the seventh time
－4 ＋7 －9 ＋8 ＋6 －5 －2
(1) How far is the end time from a?
(2) In the second record, it was farthest from a
(3) If the fuel consumption is 0.3 liters per km, how many liters is the total fuel consumption?
26. If the rational numbers a and B satisfy ∣ ab-2 ∣ + (1-B) 2 = 0, try to find + +The value of
Reference answer:
1、 Multiple choice questions: 1-8: bcaddbcb
2、 Fill in the blanks:
9. - 3; 10. Non positive; 11.; 12.2:00; 13.3.625 × 106; 14. - 9; 15.5 or - 5; 16.6
3、 Calculation questions 17. - 9; 18. - 45; 19.; 20.; 21.; 22
4、 Answer questions: 23. - 2 × 17 × 33; 24.0; 25. (1) 1 (2) 5 (3) 12.3; 26

Can you give me a rational number test paper for grade one
Please, help me think about it. The format is 1.1-10 2. Fill in the blanks 11-20 21. Calculate ① ② ③ ④ 22. Number axis 3. Application question 23-25. Thank you. If you answer well, you will get points

1、 Multiple choice questions (2 points for each question, 20 points in total)
1. The product of a rational number and its opposite number
(A) Is a positive number (b) is a negative number
(C) D is not necessarily greater than 0
2. If the product of two rational numbers is less than zero and the sum is greater than zero, then the two rational numbers ()
(A) Opposite sign (b) opposite sign and equal absolute value
(C) The sign is opposite and the absolute value of negative number is large (d) the sign is opposite and the absolute value of positive number is large
3. On the number axis, point a moves 2 units to the left to reach point B, and then moves 5 units to the right to reach point C. if the number represented by point C is 1, then the number represented by point a is ()
A．7 B．3 C．－3 D．－2
4. As shown in the figure, two points on the number axis correspond to real numbers respectively,
The following conclusion is correct ()
A． \x09\x09 B． \x09\x09
C． \x09\x09 D．
5. The following conclusion is correct ()
A. - a must be a negative number B. - | a | must be a non positive number
C. | a | must be a positive number D. | a | must be a negative number
6. It is known that a and B are rational numbers which are not zero, and when using the points on the number axis to represent a and B, it should be ()
A B C D
7. The opposite number of a number is greater than itself. The number is ()
A. Positive number B. negative number c.0 D. non negative number
8. The following relationship must be true ()
A. If a = B, then a = B
B. If a = a, then a > 0
C. If a + a = 0, then a ≤ 0
D. If a > b, then a > B
9. The sum of all integers with absolute values greater than 2 and less than 5 is ()
A.7 B.－7 C.0 D.5
The opposite of 10 is ()
A． B． C． D．2
2、 Fill in the blanks (1 point for each blank, 16 points in total)
1. Integers with absolute value greater than 1 but not greater than 3 have, and their sum is. If the distance from the point of a to the origin is 2, then a + | - a | =
2．
3. The smallest positive integer is_____ The rational number with the smallest absolute value is_____ A number with an absolute value of 3 is______ .
The number whose absolute value is equal to itself is
4． = .
5. As shown in the figure, if the number represented by point a on the number axis is a, then the distance from point a to the origin is
6． =_________ .
7. If ∣ A-4 ∣ = 4-A, then a_____ If, then a is_______
8. The opposite number of π - 3.14 is________ The opposite of. A-B is________ The opposite of. A + B is________ .
3、 Calculation questions (4 points for each question, 36 points in total)
1）25.3＋（－7.3）＋（－13.7）＋7.3
1. Represent the following numbers on the number axis: the absolute value is a negative number of 2.5, and the absolute value is a positive number of 3. (4 points)
2. Rational numbers and corresponding points on the number axis are shown in the figure: (6 points)
(1) On the number axis,; (2) try to connect the five numbers,,, 0, and with a ">" sign from large to small

How many square meters is 3.25 square meters equal to? How many square decimeters

1 * 3.25 = 3.25. This is the simplest. And 0.65 * 5 = 3.25
Please accept if you are satisfied

How many tons is 10 kg? How many square meters is one mu

10kg, etc. 0.1t
One mu is equal to about 667 square meters

How many square kilometers is 150000 square meters

1 square kilometer = 1000 meters * 1000 meters = 100 square meters
15 / 100 = 0.15 km2

How many Mu is 427.5 square meters

1 mu = 60 square feet = 667 square meters 427.5 square meters △ 667 square meters = 0.64 Mu

How many Mu is 493.5 square meters

16 Mu is 10000 square meters, 493.5 / (10000 / 16) = 0.7032 mu