What least number must be added to 15370 to make it a perfect square ?

Options

A. 4
B. 6
C. 8
D. 9

Answer

To find the least number that must be added to 15370 to make it a perfect square, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the nearest perfect square**:
We need to find the square root of 15370 to determine the nearest whole number.

\[ \sqrt{15370} \approx 123.9 \]

The nearest whole numbers are 123 and 124.

2. **Calculate the perfect squares of these whole numbers**:
- For 123:
\[ 123^2 = 15129 \]
- For 124:
\[ 124^2 = 15376 \]

3. **Determine the differences**:
- The difference between 15370 and 15129:
\[ 15370 - 15129 = 241 \]
- The difference between 15376 and 15370:
\[ 15376 - 15370 = 6 \]

4. **Identify the least number to be added**:
Since we need to make 15370 a perfect square, we compare the two differences calculated:
- To reach 15129, we would need to subtract 241 (not applicable as we need to add).
- To reach 15376, we need to add 6.

5. **Conclusion**:
The least number that must be added to 15370 to make it a perfect square is:
\[ \boxed{6} \]