√374 at a glance
- Exact value
- √374
- Decimal (10 places)
- 19.3390796058
- Rounded
- 19.3 · 19.34 · 19.339
- Perfect square?
- No — between 19² and 20²
- Rational?
- Irrational
- Both square roots
- ±19.339080
- Prime factorization
- 2 × 11 × 17
- Cube root
- 7.204832
How to simplify √374
The prime factorization of 374 is 2 × 11 × 17. Every prime appears only once, so there is no pair to bring outside the radical — √374 is already in simplest form (a "square-free" radicand).
A whole number has a rational square root only when every prime in its factorization appears an even number of times. In 374, 2, 11 and 17 appear an odd number of times, so √374 is irrational and 19.3390796058 is a rounded value.
Where √374 sits between perfect squares
361 = 19² and 400 = 20² are the nearest perfect squares, so √374 lies between 19 and 20. 374 is 13 above 361 and 26 below 400, so the root is closer to 19.
- Straight line between 361 and 400: 19.3333 (0.03% low)
- Tangent from 19, i.e. 19 + 13 ÷ 38: 19.3421 (0.02% high)
- Tangent from 20, i.e. 20 − 26 ÷ 40: 19.3500 (0.06% high)
For √374 the tangent at 19 wins, missing by only 0.003. Tangent estimates shine when the number sits close to a perfect square — here 374 is just 13 above 361.
Finding √374 with the Babylonian method
The idea is ancient. A Babylonian clay tablet catalogued as YBC 7289, about 3,800 years old, records √2 correct to roughly six decimal places, and Heron of Alexandria described this averaging rule in the first century AD.
Start from the nearest whole number, 19 (19² = 361):
| Step | Guess x | 374 ÷ x | Average | Correct decimals |
|---|---|---|---|---|
| 1 | 19.0000000000 | 19.6842105263 | 19.3421052632 | 2 |
| 2 | 19.3421052632 | 19.3360544218 | 19.3390798425 | 6 |
| 3 | 19.3390798425 | 19.3390793692 | 19.3390796058 | all 10 shown |
The count of correct decimals went 2, 6 and all 10 over 3 steps — roughly doubling each time — until the guess matched √374 = 19.3390796058 to every decimal shown.
√374 as a continued fraction
Every irrational square root has a continued fraction that repeats. For √374 the pattern is [19; 2, 1, 18, 1, 2, 38] with the block of 6 terms after the semicolon repeating forever. A pattern that never ends is one more proof that √374 is irrational.
Cutting the continued fraction off early gives the best fractions for approximating the root — no fraction with a smaller denominator comes closer:
| Fraction | Decimal | Error |
|---|---|---|
| 19/1 | 19.0000000000 | 3.4 × 10⁻¹ |
| 39/2 | 19.5000000000 | 1.6 × 10⁻¹ |
| 58/3 | 19.3333333333 | 5.7 × 10⁻³ |
| 1,083/56 | 19.3392857143 | 2.1 × 10⁻⁴ |
| 1,141/59 | 19.3389830508 | 9.7 × 10⁻⁵ |
| 3,365/174 | 19.3390804598 | 8.5 × 10⁻⁷ |
The same fractions solve Pell’s equation, x² − 374y² = 1. Its smallest solution in positive whole numbers is x = 3,365, y = 174.
√374 in geometry and everyday measurements
- A square patio or deck of 374 square feet is about 19.34 ft (19 ft 4 in) on each side, so edging all the way around takes 4 × √374 ≈ 77.4 ft.
- 374 is not a sum of two whole-number squares — the prime factor 11 (one less than a multiple of 4) appears an odd number of times, which rules that out — so √374 is never the diagonal of a rectangle with whole-number sides. It is, however, the space diagonal of a 1 × 7 × 18 box, because 1² + 7² + 18² = 374.
Square roots near √374 and related roots
| Root | Simplest form | Decimal | Perfect square? |
|---|---|---|---|
| √371 | √371 | 19.2614 | No |
| √372 | 2√93 | 19.2873 | No |
| √373 | √373 | 19.3132 | No |
| √374 | √374 | 19.3391 | No |
| √375 | 5√15 | 19.3649 | No |
| √376 | 2√94 | 19.3907 | No |
| √377 | √377 | 19.4165 | No |
- The cube root of 374 is about 7.204832.
- Squaring undoes the root: (√374)² = 374, while 374² = 139,876 — the number whose square root is 374.
Frequently asked questions
What is the square root of 374?
The square root of 374 is √374, about 19.3390796058. The negative root, −19.339080, also squares to 374.
Is the square root of 374 rational or irrational?
Irrational. 374 is not a perfect square — it falls between 361 and 400 — and the square root of any whole number that is not a perfect square cannot be written as a fraction.
Can √374 be simplified?
No. 374 = 2 × 11 × 17 has no repeated prime factor, so there is no perfect square to take out of the radical.
What is √374 rounded to two decimal places?
√374 ≈ 19.34 to two decimal places (19.3 to one, 19.339 to three). Check: 19.34² = 374.0356, close to 374.