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: