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The formula for calculating square circumference is not too difficult, when this is a basic geometry and has the simplest calculation. Only with a given square edge value will calculate the circumference. Let Mầm non Cát Linh learn more in the following article.

The formula for calculating square circumference

In the 3rd grade math program, he will learn and get used to the types of learning. In particular, the square is known as the geometry with the most memorable circumference formula in all types.

The square circumference is the length of the line surrounding a two -dimensional image, which is the 4 -sided length surrounding that image or in other words the square circumference is equal to the sum of the length of the 4 sides. Thus the formula for calculating the square circumference is:

P = ax 4

In there:

• A is the side of the square
• P is the circumference symbol

How to calculate square circumference

Want to calculate the square circumference, what should we do? As we all know, the square is a figure with four equal sides and four right angles. With the square circumference is the total length of the four square sides. So, we have details how to calculate the perimeter of the square as follows:

1. Determine the square edge length: we can measure the length of the square edge equal to the ruler or the measure or from the data that the problem has given.
2. Apply the square circumference formula: We change the square edge length to the square circumference formula P = Ax 4.
3. N multiplication of square edge with 4: We perform multiplication to calculate the circumference of the square.

For example: A square has a 5 cm long sides.

The square circumference is: P = 5 x 4 = 20.

So the circumference of the square is 20 cm.

The relationship between the circumference and the area of ​​the square

The relationship between the circumference and the square area can be understood as follows:

• The square circumference is proportional to the edge length of the square. This means that if the edge length of the square increases, the circumference of the square also increases. (Calculated formula: P = ax 4)
• The square area of ​​the square ratio is square with the edge length of the square. This means that if the edge length of the square doubles, the area of ​​the square will increase four. (Calculated formula: S = a^2)

Thus, based on the formula for calculating the circumference, the area of ​​the 4th grade square above, the square circumference doubled, the area of ​​the square increased by four. But it should be noted that this relationship is not a direct relationship between the circumference and the area, but an indirect relationship through the edge length of the square.

Some common types

After grasping the circumference formula of the square, here are some common types of relevant exercises that students need to pay attention to:

Form 1: Calculate the perimeter of the square when knowing the length of 1 edge

This is considered the most basic type of exercise when learning square math. Specifically, in this exercise, the lesson will let them know the length of the given square edge and the circumference requirements.

With this form of exercise, they only need to apply the circumference formula of the image that can be solved.

Example: Calculate the perimeter of the square ABCD with the length of the sides equal to 3cm

Solution:

The circumference of the square ABCD is: 4 x 3 = 12 (cm).

Answer: 12 cm

Form 2: Calculate the square circumference when knowing the area

How to calculate the circumference of a square when you only know its area? With the problem for the square area, requiring the circumference of the perimeter to be an advanced exercise, requiring students to flexibly apply the knowledge, the formula for the perimeter and the area of ​​the image to solve.

With this exercise, they need to remember the following formulas and knowledge:

• Formula for calculating square area: S = A2
• Collective calculation formula: P = Ax 4

In there:

• • S is the square area

  • P is the circumference symbol

  • A is the side

To solve this exercise, students can take the following two simple steps:

• Step 1: Apply the formula for calculating the square area, from which to deduce the edge length

• Step 2: From the edge length found, start applying the formula to find the correct circumference.

For example, for a square area of ​​16cm2, calculate the square circumference.

Solution:

Apply the formula to calculate the square area s = ax 2 => ax 2 = 16 => a = 4 (cm)

Apply the circumference formula: P = Ax 4 => We get the square circumference of 4 x 4 = 16cm.

Answer: 16 (cm)

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Form 3: For square circumference, calculating the length of the edge

Similar to the above article, the problem will have a square circumference and ask them to find the length of that square. To solve the exercise, you only need to apply the circumference formula to deduce how to find a simple edge length.

For example: Give a square ABCD with a circumference of 8cm, calculating the length of that square.

Solution:

We have the formula P = Ax 4 => Ax 4 = 8 => A = 8: 4 = 2.

Answer, length of square edge is 2cm.

[Tìm hiểu thêm] How different is the square and rectangular shape about the circumference?

Square and rectangular shaped are two quadrilateral, with four sides and four corners. However, these two shapes have a difference in the circumference, as easy to see as square with four equal sides, while the rectangle has two equal opposite sides and the other two sides are equal.

The formula for calculating the circumference of the rectangle is P = (A + B) x 2.

In there:

• P is a rectangular circumference
• A is the length of the rectangle
• b is the length of the rectangle

We can conclude, the square circumference depends only on the edge of the square, while the rectangular circumference depends on the length and width of the rectangle.

Exercise on the circumference of the square for your baby to practice

After grasping the theory of the circumference formula of the square, here are some exercises for them to practice themselves:

Lesson 1: Calculate the perimeter of the square with the length of the edge equal to:

a) 15 cm	b) 4 dm	c) 33 m	d) 7 m 15 dm
e) 12 dm	g) 25 cm	h) 10 m	i) 6 dm 3 cm

Lesson 2: Calculating the edge length of the square that knows the square circumference is:

a) 44 m	b) 96 cm	c) 224 dm	d) 64 dm
e) 12 cm	g) 100 m	h) 56 dm	i) 2 m 8 cm

Lesson 3: The circumference of the square has a length of 12cm:

A. 48 cm

B. 52 cm

C. 36 cm

D. 24 cm

Lesson 4: A square carpet has a 20 cm sides. The circumference of that carpet is:

A. 80 cm

B. 90 cm

C. 100 cm

D. 110 cm

Lesson 5: A square cover has a circumference of 14 dm 4 cm. The edge of that table is equal to:

A. 22 cm

B. 28 cm

C. 36 cm

D. 40 cm

Lesson 6: Calculate the square circumference that knows the square area is 36 cm2

Lesson 7: Calculate the edge of the square with a circumference of 1024m

Lesson 8: Calculate the square circumference of the edge of the 25cm long square

Lesson 9: A square with an area of ​​144cm2. Calculate the circumference of that square.

Lesson 10: Each brick has a 20cm sides. Calculate the circumference of the rectangle assembled by 3 such bricks.

The note to remember when doing the square circumference behavior

Before doing exercises about the circumference of 4th grade square, students should note a number of things to not get wrong, especially in important exams. Specifically:

• To calculate the square circumference, students need to pay attention to the measurement unit of the edges. If the edges are recorded by the same measurement unit, there is no need to change the unit. However, if the edges are recorded by different measurement units, it is necessary to change the same measurement unit before calculating.
• To accurately calculate the perimeter of the square, pay attention to simple calculations such as plus, subtract, multiply, and divide. It is necessary to perform accurate calculations to avoid errors.
• In addition to the formula for calculating square circumference, it is necessary to master the knowledge of the square area.
• Before starting to calculate, you need to read the problem carefully to understand the requirements of the exercise. Avoid the case of skimming through the problem, leading to misunderstanding the requirements of the exercises and doing wrong.

Tips to help your child do the effective square circumference exercises

With the circumference of a square, there is not too much difficult knowledge, but to help them learn to understand, do more accurate exercises, here are some secrets for parents to refer:

• Make sure your child masters the basic knowledge: With this type of exercise, parents need to ensure that they know what is square, the formula for the circumference, the area, the symbols in the formula, the steps to solve the exercise, …

• With more children practicing: practicing homework regularly regularly after each lesson, playing games related, … will increase the interest and help your memory better.

• Ask your child to read the problem carefully: With the circumference exercise, there will be many different types of math, so parents need to ask their children to analyze the problem carefully, from what the problem is? What requires? To be able to solve the most accurate math.

• Study interesting mathematics with Mầm non Cát Linh Math: This is the application of English math teaching that is trusted by millions of parents, thanks to the active teaching method for children to understand the root of the problem, learn through the game and use the supplementary exercise book. Thereby helping children master mathematical knowledge, as well as help parents are less hard in teaching children.

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Application of the square circumference formula in practice

Currently, the circumference of the square is used not only in math but also in practice. Such as:

In the field of design and geometry

Today, the determination of the circumference of the square is used to calculate many different attributes of geometry such as finding the length of diagonal lines, calculating the area, determining the angles in the square based on related formulas.

In construction and design, the circumference formula of the square is used to draw technical drawings, measure, determine the distance and size of the edge in the construction and design process.

Application in other practical problems

• Finance and business: Based on the above formula, it is possible to calculate the cost of construction materials, fences around a square land.
• Management and positioning: Based on the circumference calculation of the square, it is easy to calculate, measure or locate in the GPS geographic map system or GPS global positioning.
• Technology and programming: Some applications and software are currently applying the circumference formula of the square to create a more accurate calculation tool such as the area of ​​the square land, the image area in the image processing, etc. or the algorithms in geometric programming.

When understanding the circumference formula of geometry in general, square in particular, people will see that they are applied a lot in practice, helping to solve many problems related to squares easier.

Surely with the above sharing, they completely grasped the formula for calculating square circumference. With a simple formula, students can easily remember and apply correctly. Do not forget to choose Mầm non Cát Linh Math to make your baby’s math learning more interesting and more effective.

References

Perimeter of Square

https://byjus.com/maths/perimeter-OF-square

Perimeter of Square

https://www.cuemath.com/measurement/perimeter-OF-QUARE/

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