√776 at a glance
- Exact value
- 2√194
- Decimal (10 places)
- 27.8567765544
- Rounded
- 27.9 · 27.86 · 27.857
- Perfect square?
- No — between 27² and 28²
- Rational?
- Irrational
- Both square roots
- ±27.856777
- Prime factorization
- 2³ × 97
- Cube root
- 9.189402
How to simplify √776
Look for the largest perfect square that divides 776. Here it is 4 (2²), because 776 = 4 × 194 and 194 has no square factor left:
The prime factorization tells the same story: 776 = 2³ × 97. Each pair of equal primes leaves the radical as one factor, so 2 comes out and 2 × 97 stays inside.
Check: (2√194)² = 2² × 194 = 4 × 194 = 776. As a decimal, 2√194 = 2 × 13.9283882772 ≈ 27.8567765544.
Where √776 sits between perfect squares
729 = 27² and 784 = 28² are the nearest perfect squares, so √776 lies between 27 and 28. 776 is 47 above 729 and 8 below 784, so the root is closer to 28.
- Straight line between 729 and 784: 27.8545 (0.01% low)
- Tangent from 27, i.e. 27 + 47 ÷ 54: 27.8704 (0.05% high)
- Tangent from 28, i.e. 28 − 8 ÷ 56: 27.8571 (0% high)
For √776 the tangent at 28 wins, missing by only 0.0004. Tangent estimates shine when the number sits close to a perfect square — here 776 is just 8 below 784.
Finding √776 with the Babylonian method
Picture a rectangle with an area of 776 and one side x; the other side must be 776 ÷ x. Averaging the two sides gives a rectangle that is closer to a square, and the side of that square is exactly √776.
Start from the nearest whole number, 28 (28² = 784):
| Step | Guess x | 776 ÷ x | Average | Correct decimals |
|---|---|---|---|---|
| 1 | 28.0000000000 | 27.7142857143 | 27.8571428571 | 3 |
| 2 | 27.8571428571 | 27.8564102564 | 27.8567765568 | 8 |
| 3 | 27.8567765568 | 27.8567765520 | 27.8567765544 | all 10 shown |
The count of correct decimals went 3, 8 and all 10 over 3 steps — roughly doubling each time — until the guess matched √776 = 27.8567765544 to every decimal shown.
√776 as a continued fraction
Every irrational square root has a continued fraction that repeats. For √776 the pattern is [27; 1, 5, 1, 54] with the block of 4 terms after the semicolon repeating forever. A pattern that never ends is one more proof that √776 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 |
|---|---|---|
| 27/1 | 27.0000000000 | 8.6 × 10⁻¹ |
| 28/1 | 28.0000000000 | 1.4 × 10⁻¹ |
| 167/6 | 27.8333333333 | 2.3 × 10⁻² |
| 195/7 | 27.8571428571 | 3.7 × 10⁻⁴ |
| 10,697/384 | 27.8567708333 | 5.7 × 10⁻⁶ |
| 10,892/391 | 27.8567774936 | 9.4 × 10⁻⁷ |
The same fractions solve Pell’s equation, x² − 776y² = 1. Its smallest solution in positive whole numbers is x = 195, y = 7.
√776 in geometry and everyday measurements
- 776 square feet is 72.1 m². Laid out as a square — a small house footprint or a lot — it is about 27.86 ft (27 ft 10 in) on a side.
- 776 = 10² + 26², so by the Pythagorean theorem √776 is the diagonal of a 10 × 26 rectangle — and the distance between the points (0, 0) and (10, 26) on a grid.
- Since √776 = 2√194, a length of √776 is exactly 2 copies of the length √194 laid end to end.
Square roots near √776 and related roots
| Root | Simplest form | Decimal | Perfect square? |
|---|---|---|---|
| √773 | √773 | 27.8029 | No |
| √774 | 3√86 | 27.8209 | No |
| √775 | 5√31 | 27.8388 | No |
| √776 | 2√194 | 27.8568 | No |
| √777 | √777 | 27.8747 | No |
| √778 | √778 | 27.8927 | No |
| √779 | √779 | 27.9106 | No |
- The cube root of 776 is about 9.189402.
- Because 776 = 4 × 194, the root is twice √194: 2 × 13.928388 ≈ 27.856777.
Frequently asked questions
What is the square root of 776?
The square root of 776 is 2√194 in simplest radical form, which is about 27.8567765544. The negative root, −27.856777, also squares to 776.
Is the square root of 776 rational or irrational?
Irrational. 776 is not a perfect square — it falls between 729 and 784 — and the square root of any whole number that is not a perfect square cannot be written as a fraction.
Can √776 be simplified?
Yes. The largest perfect square dividing 776 is 4, so √776 = √4 × √194 = 2√194.
What is √776 rounded to two decimal places?
√776 ≈ 27.86 to two decimal places (27.9 to one, 27.857 to three). Check: 27.86² = 776.1796, close to 776.