The perimeter is the length of the path that outlines a shape or a two-dimensional object. The perimeter of a circle and ellipse is also called as the circumference. The calculation of a perimeter has efficient use. You can observe the use of perimeter in your day-to-day life. The perimeter of the wheel decides the length of the path covered by the motor.

 As we discussed the various practical use of the perimeter, let’s find out how to calculate the perimeter of different two-dimensional objects. 

The Perimeter Of a Rectangle: 

The rectangle is a ubiquitous shape that we came across in our daily lifestyle. The use of the perimeter often comes in case of a Rectangle. Before going more into it, let me tell you that the formula to find the perimeter of a rectangle is P = 2 ( w + h ).

 Here,

P = The Perimeter of The Rectangle

w = The width of the Rectangle

h = The height of the Rectangle

 To execute this formula, you must know the height and the width of the rectangle. 

Let’s take an example of a rectangle for a better understanding and natural solving process. Say, we have a rectangle of length 12 cm and width 6 cm. Now let’s find out the perimeter of this given rectangle.

 First of all, put the values of w & h in the respective places in the formula. After putting the values, the formula will be, 

P = 2 ( 6 + 12 ) 

Now let’s add the values inside the bracket. And multiply the result with 2. Then the equation will be, 

P = 2 X 18

= 36 cm

 Hence the perimeter of the given rectangle is 36 cm. 

In otherwise you can also add all the sides of a rectangle to find its perimeter. In this case, the formula will be, P = a + b + c + d. Where P is the perimeter of the rectangle and a,b,c,d refers to each of the sides of the rectangle.

 The Perimeter Of a Square: 

We all know that the square is a rectangle which has all the sides with the same length and at a 90° to each other. If we put the rectangular formula in calculating the perimeter of the square, it will be

 P = 2 ( a + a )

= 2 X 2a

= 4a

 For instance, if we have a square with a side length of 5 cm, then the perimeter will be 

P = 4 X 5

= 20 cm

 The Perimeter of A Circle ( The Circumference ): 

To calculate the circumference of a circle the central part is to know the radius of the circle. The formula to calculate the circumference of a circle is C = 2π X r.

 Here, C = The circumference of The Circle

r = The radius of the circle 

If you’re given a problem regarding the circumference of a circle, there will also be the radius of the circle given in the question. You can put the value of the radius and find the circumference. In case if you’re given the diameter of the circle then use this formula ( C = π X r ) to calculate the circumference.

 For Instance, let’s say we have a circle with a radius of 5 cm. Now to calculate it’s circumference we need to multiply the radius value of the circle with 2 and π. Putting the values in the equation we have, 

C = 2 X π X 5

= 10 X π

= 10 X 3.14

= 31.4 cm

 Hence the perimeter of the circle (The Circumference) is 31.4 cm.