Fourth unit

Proposer Feng, gaomi city No.2 Experimental Primary School.

First, fill in the blanks. (10)

1. The area of a square with a side length of 1 m is () square meters.

2. The commonly used area units are (), () and (), and () is commonly used to calculate the land area.

3. Area of rectangle = () × () Area of square = ()× ()

4. Fill in the appropriate unit name in brackets.

The area of a button is about 2 () The palm area of an adult is about 1 () The height of a tree is 10 () The area of the classroom is 56 ().

5.3 square meters = () square decimeter 7 square decimeter = () square centimeter

500 square decimeter = () square meters 2 square kilometers = () hectares

Second, judge. (5 points)

1. 100 hectares = 1 km2. ( )

2. A pen is 12 square decimeter long. ( )

A square with a side length of 4 cm has the same circumference and area. ( )

A rectangle with a length of 5 decimeters and a width of 4 decimeters, with an area of 20 decimeters. ( )

5. Enclose two different rectangles with two lines of equal length, and their perimeters are the same. ( )

Third, multiple choice questions. (10)

1. A handkerchief with an area of 40 square centimeters made of 80 square decimeters of cloth can be made into ().

A, 2 B, 20 C, 200 D, 2000.

2. In the figure below, the rectangle is divided into two parts, A and B, namely ().

The area and circumference are equal. Area and perimeter are not equal. C, the circumference is equal, but the area is unequal.

3. The area of two squares with equal perimeters ()

A, unequal b, equal c, not necessarily equal

4.6 square meters is equal to ().

A, 60 square decimeters b, 60 meters c, 600 square decimeters

5. The area of a square is 30 ()

A, hectare b, square meter c, square decimeter

Fourth, fill in the form according to the known conditions. (20 points)

1.

chart

long

extensive

bellyband

zone

rectangle

20 meters

15m

25 decimetres

70 decimeters

2.

chart

Length of side

bellyband

zone

square

5 decimeters

20 decimeters

8 cm

Verb (abbreviation of verb) fill in ">"

60 square centimeters, 6 square decimeters, 5 hectares and 4,900 square meters.

300 hectares, 3 square kilometers, 5 square meters and 500 square centimeters.

300 square decimeters, 3 square meters, 800 meters and 6 kilometers

Sixth, operational issues. (8 points)

1, and the area of each small square represents 1 cm2. Write down the area below.

() square centimeter () square centimeter

2. Draw a rectangle with a length of 4 cm and a width of 2 cm.

Sixth, the calculation problem.

1.(5 points) The side length of a square handkerchief is 30 cm. How many square centimeters is its area? How many square decimetres?

2.(6 points) A rectangular vegetable field, 40 meters long and 20 meters wide. What is the area and perimeter of this rectangular vegetable field?

3.(5 points) The wall in front of the classroom is 7 meters long and 4 meters wide. There is a blackboard with an area of 4 square meters on the wall. What is the area of the wall in front of the classroom to be painted?

4.(5 points) There is a classroom, 8 meters long and 2 meters wide. What is the area of this classroom?

5.(5 points) The length of the rectangle is 20cm and the width is12cm. What is the area of the largest square cut from this rectangle? What's the remaining area?

6.(8 points) Calculate the area of the land shown on the right.

7.(9 points) A house is 6 meters long and 4 meters wide. How many square meters should the floor of this house be paved? If the area of each tile is 4 square decimeters, how many tiles does the house need?