For the following, find the least number that must be added so that the resulting number is a perfect square 511.
511 Taking square root of 511, we find that 27 has been left We see that 511 is greater than (22)2
| | 22 | | 2 | 5 114 | | 42 | 11184 | | | 27 |
On adding the required number to 511, we get (23)2i.e., 529 So, the required number = 529 511 = 18