Current location - Training Enrollment Network - Mathematics courses - Classroom exercises 1 15 Mathematics Page 4 Answers People's Education Edition
Classroom exercises 1 15 Mathematics Page 4 Answers People's Education Edition
First, multiple-choice questions (5 points for each small question, 30 points for * * *):

1, and the three points A, B and C on the known number axis represent rational numbers respectively.

, 1,-1, then

Represents (

)

(a) The distance between point A and point B.

(b) the distance between point a and point c.

(c) The sum of the distances from point A and point B to the origin.

(d) The sum of the distances from point A and point C to the origin.

2. Wang Laobo first bought five sheep in the market, with an average of each sheep.

Yuan, and later bought three sheep, each on average.

Yuan and Hou

Come on, he uses everyone.

The selling price of all the sheep turned out to be a loss. The reason for the loss is (

)

(1)

(2)

(3)

(d) with

Regardless of size.

3. The sum of two positive numbers is 60, and their least common multiple is 273, so their product is (

)

273 copies

(b)8 19

(c) 1 199

19 1 1

4. A class of ***48 people went boating on the West Lake in Hangzhou in the spring, with 3 people per boat, and the rent was 16 yuan, with 5 people per big boat.

People, rent 24 yuan, then this class should at least spend rent (

)

(1) 188 yuan

192 yuan

232 yuan

240 yuan

5, the perimeter of the known triangle is

One side is twice as big as the other, and the range of the smallest side of the triangle is (

)

(1)

and

amongst

(2)

and

amongst

(3)

and

amongst

(4)

and

amongst

6. Two identical bottles are filled with alcohol solution, and the volume ratio of alcohol and water in one bottle is.

: 1, in another bottle

The volume ratio of alcohol to water

: 1, two bottles of solution are mixed together, and the volume ratio of alcohol to water in the mixed solution is.

(

)

(1)

(2)

(3)

(4)

II. Fill in the blanks (5 points for each small question, 30 points for * * *):

7. Known

, and

>

>

, then

=

8. Set the polynomial

, known time

= 0,

; while

When,

Zedang

When,

=

9. Arrange positive and even numbers into 5 columns according to the table below:

Column 1

The second column

The third column

Column 4

The fifth column

top row

2

four

six

eight

Something prepared

16

14

12

10

Third line

18

20

22

24

Fourth line

32

30

28

26

……

According to the rules in the table, even number 2004 should be ranked first.

Okay, the first one

Column;

10, Party A and Party B set off at the same time with their backs to point A on the 400m circular runway. Eight minutes later, they met for the fifth time.

It is known that A walks 0. 1 m more than B every second. What is the shortest distance along the runway from where they met for the fifth time to point A?

Rice;

1 1. Someone asked Teacher Yang, "How many students are there in your class?" Teacher Yang said: "Now half of the students in our class are taking part in the math contest, one quarter are taking part in the music interest group, one seventh are in the reading room, and three female students are watching TV." . What is the number of students in Miss Yang's class?

12. There are two red balls and two white balls in the box. Xiaoling touched the balls out of the box one by one, and red balls and white balls alternated.

The possibility of occurrence (which can be "red, white, red and white" or "white, red, white and red") is

Third, answer questions:

13, (10) as shown in the figure, ab‖ed, ∠ C = known.

,∠abc=∠def,∠d=

,∠f=

Find the size of e.

14, (10 minute) The midline of the waist of an isosceles triangle divides the perimeter of the triangle into 14.

And 18

Two parts, three parts.

The length of each side of an angle.

15 and (10) have nine straight lines on the plane, and no three straight lines intersect at one point. What is the positional relationship of these nine straight lines, so that their intersection point is exactly 26, and all possible situations can be drawn (it is required to draw correctly with a ruler).

16, (10 minute) The three hands of the clock coincide at 12. How many minutes did it take the second hand to set the angle of the minute hand and the hour hand for the first time?

Acute angle) equally divided? (expressed in fractions)

Reference answers to the 2004 Fuyang Junior One Mathematics Competition

First, multiple-choice questions (5 points for each small question, 30 points * * *): babcad

II. Fill in the blanks (5 points for each small question, 30 points for * * *):

7, 0 or -2

8、- 17

9、25 1

,3

10、 176

1 1、28

12、

Third, answer questions:

13, solution: extend dc and ab to g.

∫ed‖ab

,∠d=

∴∠g=

∫∠BCD = =

,∠bcd=∠g+∠cbg

∴∠cbg=

∴∠abc=

That is, ∠ e =

14, solution: Let the waist length of an isosceles triangle be

, the length of the bottom is

rule

or

Solution:

or

The length of the three sides of a triangle is:

Or 12,12,8.

15, solution: There are two situations, as follows:

16, Solution: Obviously, the second hand bisected the angle between the minute hand and the hour hand for the first time after 1 minute.

set up

Minutes, the second hand bisects the angle of the minute hand and the hour hand for the first time, so the angle of the hour hand is

Degree, the minute hand rotation angle is

Degree, the angle of the second hand is

degree

So there are: