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553 LearnersLast updated on August 5, 2025

The square root of 120 is 10.954. Finding the square root of a number is the inverse process of finding the perfect square. The square root of 120 is written as √120.
The different ways to find the square root of a number are prime factorization, long division and approximation/estimation method
The prime factorization of 120 breaks 120 into its prime numbers.
The numbers 2, 3, and 5 are the prime numbers .
Prime factorization of 120 is 23 × 31× 51.
Since 2 is repeating, we should pair them. We can’t pair 3 and 5 because they are not repeating.
Therefore, √20 is expressed as 2x√2 x √3 x√5, the simplest radical form.


The long division method finds the square root of non-perfect squares.
The long division method finds the square root of non-perfect squares.
Step 1: Write down the number 120
Step 2: Number 120 is a three-digit number, so pair them as (1), (20)
Step 3: Find the largest that is closest to the first pair (1), which is 12
Step 4: Write down 1 as the quotient, which will be the first digit of the square root.
Step 5: Subtracting 12 from 1 will leave zero as the remainder. Now bring down the second pair (20) and place it beside 0.
Step 6: Now double the quotient you have, that is multiply the quotient 1 with 2 and the result will be 2
Step 7: Choose a number such that it can be placed after 2. The two-digit number created should be less than the second pair (20). Here, we place 0 after 2, because the number formed will be greater than 20.
Step 8: Subtract 0 from 20 → 20-0 =20. Now add a decimal point after the new quotient and adding two zeros will make it 2000
Step 9: Apply step 7 over here and continue the process until you reach 0.
Step 10: We can write √120 as 10.954
The approximation method finds the estimated square root of non-perfect squares.
Step 1: Identify the closest perfect square to 120. Numbers 100 and 121 are the closest perfect square to 120.
Step 2: We know that √100 = 10 and √121 = 11. Thus, we can say that √120 lies between 10 and 11.
Step 3: Check if √120 is closer to 10 or 11. Let us take 10.5 and 11. Since (10.5)2 is 110.25 and (11)2 is 121, √120 lies between them.
Step 4: We can keep changing the values of 10.5 to 10. 6 and iterate the same process without changing 12 as the closest perfect square root.
The result of √120 will be 10.954
Take a look at mistakes a child can make while finding the square root of 120:
Find the value of (√120)⁴
Value of (√120)4 = 14115.8
(√120)4 = √120 x √120 x √120 x √120 = 10.9 × 10.9 × 10.9 × 10.9 = 14115.8
Calculate the perimeter of the square having an area of 120 square units
Perimeter of the square = 43.817
Square has 4 sides. So, the length of each side is √120. To find the perimeter of a square, multiply 4 with √120 → 4 x √120 = 43.817
What is the value of √119 and √120 when added together?
The sum of √119 and √120 is 21.862
√119 is 10.908 and √120 is 10.954. So, adding √119 and √120 will give the sum of 21.862
If x = √120, what is the value of x²?
The value of x2 = 120
When the square root gets squared, the root gets canceled. Here, x = √120 and x2 = (√120)2 = 120.

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.






