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In the vast realm of geometry, understanding the concept of perimeter is essential. Whether you’re a high school student navigating math class or simply curious about the world of shapes, mastering the calculation of a rectangle’s perimeter is a fundamental skill. In this article, we will explore the basic formula and provide a step-by-step guide to help you calculate the perimeter of a rectangle with ease.

Formula Explanation

Before we dive into the practical application, let’s start with a clear understanding of what perimeter means. In geometry, the perimeter refers to the total distance around the outer boundary of a two-dimensional shape. For a rectangle specifically, the formula to calculate its perimeter is simple and straightforward: 2 * length + 2 * width.

To break it down further, the formula adds up the lengths of all four sides of the rectangle. Since a rectangle has two pairs of equal sides (length and width), we multiply each value by 2 and then sum them together.

Step-by-Step Guide

Now that we have a grasp of the formula, let’s walk through a step-by-step guide on how to calculate the perimeter of a rectangle.

Step 1: Measure the length and width of the rectangle using a ruler or measuring tape.

Step 2: Plug the values obtained in Step 1 into the formula: 2 * length + 2 * width.

Step 3: Perform the necessary calculations by multiplying the length by 2, multiplying the width by 2, and then summing the two results together.

Step 4: Finalize and interpret the result as the perimeter of the rectangle.

Example Problems and Solutions

To solidify your understanding of the process, here are a few example problems with their solutions:

Example 1:

Problem: Assume you have a rectangle with a length of 8 units and a width of 3 units. Calculate the perimeter.


  • Step 1: Identify the length and width. (Length = 8 units, Width = 3 units)
  • Step 2: Apply the formula: 2 * length + 2 * width.
  • Step 3: Calculate: 2 * 8 + 2 * 3 = 16 + 6 = 22 units.
  • Step 4: The perimeter of the rectangle is 22 units.

Example 2:

Problem: A rectangular garden measures 14 meters in length and 6 meters in width. What is the perimeter of the garden?


  • Step 1: Note down the measurements. (Length = 14 meters, Width = 6 meters)
  • Step 2: Use the formula: 2 * length + 2 * width.
  • Step 3: Perform the calculation: 2 * 14 + 2 * 6 = 28 + 12 = 40 meters.
  • Step 4: Therefore, the perimeter of the garden is 40 meters.


Calculating the perimeter of a rectangle is a foundational skill in geometry. By understanding the basic formula and following a step-by-step guide, you can confidently determine the total distance around a rectangle’s outer boundary. An online math tutor can help you gain a solid understanding of this formula, and move on to more difficult math concepts!

So, whether you’re solving math problems or simply exploring the world of shapes, keep in mind the simple formula: 2 * length + 2 * width. With practice and familiarity, you’ll find yourself effortlessly calculating perimeters and unlocking the wonders of geometry.