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Last updated on August 5, 2025

Square Root of 0.8

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What is the Square Root of 0.8?

The square root is the inverse of the square of the number. 0.8 is not a perfect square. The square root of 0.8 is expressed in both radical and exponential form. In the radical form, it is expressed as √0.8, whereas (0.8)^(1/2) in the exponential form. √0.8 ≈ 0.89443, which is an irrational number because it cannot be expressed in the form of p/q, where p and q are integers and q ≠ 0.

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Finding the Square Root of 0.8

The prime factorization method is used for perfect square numbers. However, the prime factorization method is not used for non-perfect square numbers where long-division and approximation methods are used. Let us now learn the following methods:

 

  • Prime factorization method
     
  • Long division method
     
  • Approximation method
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Square Root of 0.8 by Prime Factorization Method

The product of prime factors is the prime factorization of a number. For 0.8, we can express it as a fraction (8/10) or (4/5). Since 0.8 is not a perfect square, the prime factorization approach is not straightforward for decimal or fraction values without converting to a base that can be factored easily.

Hence, the prime factorization method is not typically used for decimals like 0.8.

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Square Root of 0.8 by Long Division Method

The long division method is particularly useful for non-perfect square numbers. Here's how to find the square root using the long division method, step by step:

 

Step 1: Begin by considering 0.8 as 80/100 or 0.80 for ease of calculation.

 

Step 2: Start with the closest perfect square less than 80, which is 64 (√64=8).

 

Step 3: Use the long division method to find √0.80, bringing down pairs of zeros as needed to find more decimal places.

 

Step 4: Continue the division process until you reach the desired precision.

 

Step 5: The result will be √0.8 ≈ 0.89443.

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Square Root of 0.8 by Approximation Method

The approximation method is another method for finding square roots, useful for gaining a quick estimate. Here's how to find the square root of 0.8 using approximation:

 

Step 1: Identify perfect squares around 0.8. The closest perfect squares are 0.64 (0.8²) and 1 (1²), which are near 0.8.

 

Step 2: Recognize that √0.64 = 0.8 and √1 = 1, so √0.8 falls between 0.8 and 1.

 

Step 3: Use an average method or linear interpolation to find a closer approximation if necessary.

 

Step 4: The approximated value is √0.8 ≈ 0.89443.

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Common Mistakes and How to Avoid Them in the Square Root of 0.8

Students often make mistakes while finding square roots, such as overlooking the negative square root or misapplying methods. Let's examine a few common errors in detail.

Mistake 1

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Forgetting about the negative square root

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It's important to remember that a number has both positive and negative square roots. However, we typically use only the positive square root in practical applications.

 

For example: √0.8 ≈ 0.89443, but there is also -0.89443.

Mistake 2

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Not adding the square root symbol in proper places

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Another common mistake is misusing the square root symbol. It's crucial to simplify the numbers inside the square root before proceeding.

 

For example: √(0.4 + 0.4) = √0.8 is correct, not √0.4 + √0.4.

Mistake 3

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Not finding the correct value of a non-perfect square

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It's crucial to simplify numbers inside the square root to avoid mistakes in identifying approximate values.

 

For example: √0.8 ≠ 0.9. The correct answer is √0.8 ≈ 0.89443.

Mistake 4

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Confusing the square root symbol with the cube root

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Students must understand the difference between cube root and square root to avoid mistakes.

 

For example: √0.8 and ∛0.8 are different.

Mistake 5

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Making mistakes in long division

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Finding a square root using the long division method involves many steps. Students might skip a step accidentally, leading to a wrong answer. This can occur in subtraction or elsewhere.

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Square Root of 0.8 Examples

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Max, the Girl Character from BrightChamps

Problem 1

Can you help Max find the area of a square box if its side length is given as √0.8?

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Okay, lets begin

The area of the square is approximately 0.8 square units.

Explanation

The area of a square = side².

The side length is given as √0.8.

Area of the square = (√0.8)² = 0.8.

Therefore, the area of the square box is approximately 0.8 square units.

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Problem 2

A square-shaped garden measuring 0.8 square meters is built; if each of the sides is √0.8, what will be the square meters of half of the garden?

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0.4 square meters

Explanation

Divide the given area by 2 as the garden is square-shaped.

Dividing 0.8 by 2, we get 0.4. So, half of the garden measures 0.4 square meters.

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Problem 3

Calculate √0.8 × 5.

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Approximately 4.47215

Explanation

The first step is to find the square root of 0.8, which is approximately 0.89443.

The second step is to multiply 0.89443 by 5. So, 0.89443 × 5 ≈ 4.47215.

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Problem 4

What will be the square root of (0.6 + 0.2)?

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Okay, lets begin

The square root is approximately 0.89443.

Explanation

To find the square root, first find the sum of (0.6 + 0.2). 0.6 + 0.2 = 0.8, and then √0.8 ≈ 0.89443.

Therefore, the square root of (0.6 + 0.2) is approximately ±0.89443.

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Problem 5

Find the perimeter of a rectangle if its length ‘l’ is √0.8 units and the width ‘w’ is 0.5 units.

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Okay, lets begin

The perimeter of the rectangle is approximately 2.78886 units.

Explanation

Perimeter of the rectangle = 2 × (length + width).

Perimeter = 2 × (√0.8 + 0.5) = 2 × (0.89443 + 0.5) = 2 × 1.39443 ≈ 2.78886 units.

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FAQ on Square Root of 0.8

1.What is √0.8 in its simplest form?

The decimal 0.8 can be expressed as a fraction 4/5. The simplest form of √0.8 ≈ 0.89443.

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2.Can 0.8 be a perfect square?

No, 0.8 is not a perfect square. Perfect squares are numbers like 1, 4, 9, etc., which have integer roots.

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3.Calculate the square of 0.8.

We get the square of 0.8 by multiplying the number by itself, that is 0.8 × 0.8 = 0.64.

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4.Is 0.8 a rational number?

Yes, 0.8 is a rational number because it can be expressed as the fraction 4/5.

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5.What are the factors of 0.8?

Since 0.8 is not an integer, we typically consider its fractional equivalent, 8/10 or 4/5. The factors of the numerator 4 are 1, 2, and 4.

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Important Glossaries for the Square Root of 0.8

  • Square root: A square root is the inverse of a square. Example: 4² = 16 and the inverse is √16 = 4.

 

  • Irrational number: An irrational number cannot be written in the form of p/q, where p and q are integers, and q is not zero.

 

  • Rational number: A number that can be expressed as a fraction p/q, where p and q are integers, and q is not zero.

 

  • Decimal: A number with a whole number and a fractional part separated by a decimal point, such as 0.8.

 

  • Approximation: Estimating a number to a certain degree of accuracy, often used for non-perfect squares or irrational numbers.
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Vikrant Sharma

About the Author

Vikrant Sharma 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.

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