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132 LearnersLast updated on December 15, 2025

If a number is multiplied by itself, the result is a square. The inverse of the square is a square root. The square root is used in various fields such as vehicle design, finance, etc. Here, we will discuss the square root of 4/81.
The square root is the inverse of the square of the number.
4/81 is a perfect square.
The square root of 4/81 is expressed in both radical and exponential form.
In radical form, it is expressed as √(4/81), whereas it is expressed as (4/81)(1/2) in exponential form. √(4/81) = 2/9, which is a rational number because it can be expressed in the form of p/q, where p and q are integers and q ≠ 0.
The methods to find the square root of a fraction like 4/81 are straightforward since it is a perfect square.
Let us now learn the method:
The product of prime factors is the prime factorization of a number.
Now let us look at how 4/81 is broken down into its prime factors.
Step 1: Finding the prime factors of 4 and 81 4 = 2 × 2 81 = 3 × 3 × 3 × 3
Step 2: Now that we have found the prime factors, we pair them. 4 = 2² 81 = 3โด
Step 3: Calculate the square root of each to find the square root of the fraction: √(4/81) = √4 / √81 = (2/3) × (1/3) = 2/9


Students often make mistakes while finding the square root, such as confusing the square root with other operations.
Let us look at a few of those mistakes in detail.
Students can make mistakes while finding the square root, such as forgetting about the negative square root.
Here are a few common mistakes and tips on how to avoid them.
Can you help Max find the area of a square box if its side length is given as โ(4/81)?
The area of the square is 4/81 square units.
The area of the square = side².
The side length is given as √(4/81).
Area of the square = (√(4/81))² = (2/9)² = 4/81.
Therefore, the area of the square box is 4/81 square units.
A square-shaped tile measures 4/81 square feet; if each side is โ(4/81), what will be the square feet of half of the tile?
2/81 square feet
We can divide the given area by 2 as the tile is square-shaped.
Dividing 4/81 by 2 = 2/81.
So half of the tile measures 2/81 square feet.
Calculate โ(4/81) ร 9.
2
The first step is to find the square root of 4/81, which is 2/9.
The second step is to multiply 2/9 by 9.
So (2/9) × 9 = 2.
What will be the square root of (4/81 + 5/81)?
The square root is √(9/81), which is 1/3.
To find the square root, first find the sum of (4/81 + 5/81).
(4/81 + 5/81) = 9/81, and then √(9/81) = 1/3.
Therefore, the square root of (4/81 + 5/81) is ±1/3.
Find the perimeter of a rectangle if its length โlโ is โ(4/81) units and the width โwโ is 2 units.
We find the perimeter of the rectangle as 20/9 units.
Perimeter of the rectangle = 2 × (length + width)
Perimeter = 2 × (√(4/81) + 2)
= 2 × (2/9 + 2)
= 2 × (2/9 + 18/9)
= 2 × 20/9 = 40/9 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.






