Test paper and answer of unit 3 in the first volume of mathematics in the fourth grade of primary school

First, fill in the blanks.

1, put the serial number in brackets.

In the figure, () is a straight line, () is a ray, and () is a line segment.

2. There is one () angle and two () angles on the triangle; There is a () corner and two () corners on the red scarf.

3. Measure an angle. One side of the angle faces the inner circle scale "180" on the protractor, and the other side faces the inner circle scale "60". This angle is () degrees.

4. At 9 o'clock on the clock face, the angle formed by the hour hand and the minute hand is (); On the clock face, the hour hand walks () hours to form a rounded corner; The minute hand moves () minutes to form a right angle.

5. The length of () connecting two points is () between these two points.

6. 1 fillet = () flat angle = () right angle.

1 straight angle = () right angle

7. There are () rays in the above picture, forming () angles.

2. Fill in the following corners in the appropriate circle.

92 34 1 15 86 15 12 1

135 90 64 160 39 99

Third, judge the question. (Draw "√" on the right and "×" on the wrong)

1 and the angle. Those greater than 90 are called obtuse angles. ( )

2. The longer the side of the angle is drawn, the bigger the angle is. ( )

3. The degree of obtuse angle must be greater than that of acute angle. ( )

4. Ray is shorter than straight line, and the line segment is the shortest. ( )

5. Round corners are rays and right angles are straight lines. ( )

Fourth, multiple choice questions. (Put the serial number of the appropriate answer in brackets)

1, () energy is its length, () has no end, and () can extend to one end indefinitely.

A. line segment b-ray

C. straight line D. curve

2. From 3:00 to 3: 15, the minute hand turned ().

A. 15

C.90 D. 120

3. Among the following angles, the angle of () can be drawn by a set of triangles.

C. 15 D.20

5. How many corners can you find in the picture below?

Sixth, operational issues.

1, draw a 3 cm line segment and extend it into a ray.

2. Measure the degrees of the following angles with a protractor.

3. Draw an angle of 65 degrees with a protractor.

4. Draw the angles of 150 and 15 with a set of triangles.

Please divide the first boxer into three parts and the second boxer into four parts by triangle.

6. There are four points below. How many lines can you draw after two o'clock? Please draw a picture.

Seven, solve the problem.

1. How many angles are there in the picture below?

There are () corners, () corners and () corners.

The number of sides is 2345. ...

Number of angles ...

What did you find?

2. Draw a corner on a rectangular piece of paper, but the paper is torn and the corner is incomplete (as shown below). Can you measure its degree? Have a try.

3. When10am, what is the angle formed by the hour hand and the minute hand? At 5 pm, what is the angle between the hour hand and the minute hand?

4. Xiaojun said, "There is an angle, which can be measured twice with an angle on a triangle. This angle is an acute angle." How big is this angle?

Reference answer:

I. 1. ①, ⑤ 4②, ⑤ 2. Straight and sharp, blunt and sharp.

3. 120 4. Straight line 12 30

5. Line segment distance 6.2 4 2 7.4 6

2. Acute angle: 34,86,15,64,39 Right angle: 90.

Oblique angle: 92, 1 15, 12 1, 135,160,99.

Third, 1.×? 2.×? 3.√ 4.× 5.×

Four. 1. A, B, C and B. C 3。 C

Verb (abbreviation of verb) 9 8

6.2.48 1 10 100 82