Find the least number which must be added to `18,265` to obtain a perfect square.

Answer

To find the least number that must be added to `18,265` to obtain a perfect square, we can follow these steps:

### Step 1: Estimate the square root of 18,265
First, we need to find the approximate square root of `18,265`. We can do this by finding the nearest perfect squares around this number.

- The square of `135` is `135^2 = 18,225`.
- The square of `136` is `136^2 = 18,496`.

Since `18,225` is less than `18,265` and `18,496` is greater than `18,265`, we know that the perfect square we are looking for is between `135^2` and `136^2`.

### Step 2: Calculate the difference from the next perfect square
Next, we need to find the difference between `18,265` and the next perfect square, which is `136^2 = 18,496`.

\[ 18,496 - 18,265 = 231 \]

### Step 3: Conclusion
Thus, the least number that must be added to `18,265` to obtain a perfect square is `231`.

### Summary
The answer is:
\[ \text{Least number to be added} = 231 \]

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