Square root of 55
√55 ≈ 7.4162. The square root of 55 is about 7.4162. 55 is not a perfect square, so √55 is irrational: its decimals never end or repeat.
| Value | 7.41619849 |
|---|---|
| Rounded | 7.4 (1 dp) · 7.42 (2 dp) · 7.416 (3 dp) |
| Simplest radical form | √55 |
| Perfect square? | No — between 7² = 49 and 8² = 64 |
| 55 squared | 3,025 |
Estimating √55 in your head
Start from the nearest perfect square, 7² = 49. 55 is 6 more than that. Divide the difference by twice the root, 14, and add it:
√55 ≈ 7 + 6 ÷ 14 ≈ 7.429
The true value is 7.4162, so the one-step estimate is off by about 0.012. The estimate always comes out slightly high, and it is closest when 55 is near a perfect square. The method is explained in estimating square roots in your head.
Can √55 be simplified?
No. 55 has no perfect-square factor besides 1, so √55 is already in simplest radical form.
Frequently asked questions
What is the square root of 55?
The square root of 55 is about 7.4162. 55 is not a perfect square, so √55 is irrational: its decimals never end or repeat.
Is 55 a perfect square?
No. It lies between 7² = 49 and 8² = 64.
What is √55 in simplest radical form?
√55 is already in simplest form: 55 has no square factor other than 1.
Practise estimating square rootsNearby: √54 · √56 · all square roots to 150