The least number which must be added to 1200 so that the sum is a perfect square is

Options

A. 52
B. 25
C. 35
D. 45

Explanation

To find the least number that must be added to 1200 so that the sum is a perfect square, we can follow these steps:

### Step 1: Identify the nearest perfect square greater than 1200
First, we need to find the square root of 1200 to determine the nearest perfect square.

\[ \sqrt{1200} \approx 34.64 \]

The next whole number after 34.64 is 35.

### Step 2: Calculate the perfect square of 35
Now, we calculate the perfect square of 35:

\[ 35^2 = 1225 \]

### Step 3: Find the difference between 1225 and 1200
Next, we subtract 1200 from 1225 to find out how much we need to add:

\[ 1225 - 1200 = 25 \]

### Conclusion
Thus, the least number that must be added to 1200 to make it a perfect square is **25**.

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