√155 ≈ 12.4499
√155 is an irrational number, so its decimals never end or repeat. It sits between 12 and 13 because 12² = 144 and 13² = 169.
| Decimal places | Value |
|---|---|
| 0 | 12 |
| 1 | 12.4 |
| 2 | 12.45 |
| 3 | 12.450 |
| 4 | 12.4499 |
| 5 | 12.44990 |
| 10 (digits) | 12.4498995980 |
155 has no perfect-square factor other than 1, so √155 is already in simplest radical form.
12.4499 × 12.4499 ≈ 155.0000, which is very close to 155.
Need another number? Use the square root calculator (also cube roots and other roots).
| Number | Square root |
|---|---|
| 151 | 12.2882 |
| 152 | 12.3288 |
| 153 | 12.3693 |
| 154 | 12.4097 |
| 156 | 12.4900 |
| 157 | 12.5300 |
| 158 | 12.5698 |
| 159 | 12.6095 |