Square Root of 125

Calculate √125 instantly — exact value, step-by-step explanation, and properties.

√125 =
11.1803398875
Simplified: 5√5
≈ Irrational Number

How to Calculate √125

The square root of 125 is approximately 11.1803398875. Since 125 is not a perfect square, its square root is an irrational number. We know that √121 = 11 and √144 = 12, so √125 falls between 11 and 12. The simplified radical form is 5√5. To estimate manually: start with 11.1, then refine using the Babylonian method — guess a value, divide 125 by it, average the result with your guess, and repeat.

The Babylonian Method (Step by Step)

  1. Start with an initial guess. Since √121 = 11 and √144 = 12, a good starting guess is 11.5.
  2. Divide 125 by your guess: 125 ÷ 11.5 = 10.8696
  3. Average the result with your guess: (11.5 + 10.8696) ÷ 2 = 11.184783
  4. Repeat with the new estimate until you reach the desired precision.
√125 ≈ 11.1803398875

Properties of √125

Perfect Square?

No

125 is not a perfect square. Its root is irrational.

Decimal Value

11.1803398875

Rounded to 10 decimal places.

Simplified Form

5√5

Simplified by extracting perfect square factors from the radicand.

Square Root Symbol

√125

Also written as 125^(1/2) or 125^0.5 in programming.

Related Square Root Values

Reference table of square roots near 125 for quick comparison.

Number Square Root Perfect Square? Simplified
√121 11 Yes 11
√144 12 Yes 12
√100 10 Yes 10
√150 12.247448 No 5√6
√90 9.486832 No 3√10
√81 9 Yes 9
√169 13 Yes 13
√80 8.944271 No 4√5
√75 8.660254 No 5√3
√72 8.485281 No 6√2

Frequently Asked Questions

What is the square root of 125?

The square root of 125 is approximately 11.1803398875. This is an irrational number, which can be written in simplified radical form as 5√5.

Is 125 a perfect square?

No, 125 is not a perfect square. Its square root (11.1803398875...) is an irrational number that cannot be expressed as a simple fraction.

How do you calculate √125 by hand?

To calculate √125 by hand, use the Babylonian method: (1) Make an initial guess — since √121 = 11 and √144 = 12, start with 11.5. (2) Divide 125 by your guess. (3) Average the result with your guess. (4) Repeat steps 2-3 until you reach desired precision.

What is √125 in simplified radical form?

√125 can be simplified to 5√5. This is found by factoring out the largest perfect square from 125.

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