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345 LearnersLast updated on August 5, 2025

The square root is the inverse operation of squaring a number. 404 is not a perfect square. The square root of 404 can be expressed in both radical and exponential form. In radical form, it is expressed as √404, whereas (404)^(1/2) is the exponential form. √404 ≈ 20.099, which is an irrational number because it cannot be expressed as a fraction p/q, where p and q are integers and q ≠ 0.

The prime factorization method is used for perfect square numbers. However, for non-perfect square numbers, the long division method and approximation method are used. Let's learn these methods:
The product of prime factors represents the prime factorization of a number. Let's see how 404 is broken down into its prime factors:
Step 1: Finding the prime factors of 404
Breaking it down, we get 2 x 2 x 101: 2² x 101
Step 2: Since 404 is not a perfect square, its prime factors cannot be grouped into pairs. Therefore, calculating √404 using prime factorization directly is not feasible.


The long division method is useful for non-perfect square numbers. We need to find the closest perfect square number to 404. Here's how to find the square root using the long division method, step by step:
Step 1: Group the digits of 404 from right to left. In this case, we group it as 04 and 4.
Step 2: Find n, whose square is less than or equal to 4. Here, n is 2, since 2² = 4.
Step 3: Subtract 4 from 4, the remainder is 0. Bring down 04 to make the new dividend 4.
Step 4: Double the divisor (2) and write it as 4.
Step 5: Find a digit, n, such that 4n × n ≤ 400. Here, n is 0, since 40 × 0 = 0, which is ≤ 4.
Step 6: Subtract 0 from 4, the remainder is 4.
Step 7: Add a decimal point and bring down two zeros to make the new dividend 400.
Step 8: Now, find a new digit, n, such that 40n × n ≤ 400. Here, n is 9, since 409 × 9 = 3681, which is ≤ 4000.
Step 9: Continue these steps until you achieve two decimal places.
The approximate square root of 404 is 20.099.
The approximation method is another way to find square roots, especially for non-perfect squares. Here's how to approximate the square root of 404:
Step 1: Find the closest perfect squares around 404.
The closest perfect squares are 400 (20²) and 441 (21²). Therefore, √404 is between 20 and 21.
Step 2: Use linear approximation: (Given number - smaller perfect square) / (Larger perfect square - smaller perfect square) (404 - 400) / (441 - 400) = 4 / 41 ≈ 0.098.
Add this to the lower square root: 20 + 0.098 = 20.098.
Thus, √404 ≈ 20.098.
Students may make mistakes while finding the square root, such as forgetting about the negative square root or skipping steps in the long division method. Let's explore a few common mistakes and how to avoid them.
Can you help Max find the area of a square box if its side length is given as √404?
The area of the square is 404 square units.
The area of a square = side².
The side length is given as √404. Area of the square = (√404)² = 404.
Therefore, the area of the square box is 404 square units.
A square-shaped building measuring 404 square feet is built; if each side is √404, what will be the square feet of half of the building?
202 square feet.
Since the building is square-shaped, divide the total area by 2.
404 / 2 = 202. So, half of the building measures 202 square feet.
Calculate √404 × 5.
100.495
First, find the square root of 404, which is approximately 20.099.
Then, multiply 20.099 by 5: 20.099 × 5 ≈ 100.495.
What will be the square root of (200 + 204)?
The square root is 20.
First, find the sum of (200 + 204): 200 + 204 = 404.
The square root of 404 is approximately ±20.099.
Therefore, the square root of (200 + 204) is ±20.099.
Find the perimeter of a rectangle if its length ‘l’ is √404 units and the width ‘w’ is 50 units.
The perimeter of the rectangle is approximately 140.198 units.
Perimeter of a rectangle = 2 × (length + width).
Perimeter = 2 × (√404 + 50) ≈ 2 × (20.099 + 50) = 2 × 70.099 ≈ 140.
198 units.

Jaskaran Singh Saluja is a math wizard with nearly three years of experience as a math teacher. His expertise is in algebra, so he can make algebra classes interesting by turning tricky equations into simple puzzles.
: He loves to play the quiz with kids through algebra to make kids love it.






