What is the least number to be subtracted from 2486 to make it a perfect square ?

Options

A. 85
B. 90
C. 95
D. 80

Explanation

To find the least number to be subtracted from 2486 to make it a perfect square, we can follow these steps:

### Step 1: Identify the nearest perfect square
First, we need to find the square root of 2486 to determine the nearest perfect square.

\[ \sqrt{2486} \approx 49.86 \]

### Step 2: Determine the closest perfect squares
The closest integers to 49.86 are 49 and 50. We will calculate the squares of both:

\[ 49^2 = 2401 \]
\[ 50^2 = 2500 \]

### Step 3: Compare the perfect squares with 2486
Now, we compare 2486 with the two perfect squares we calculated:

- \(49^2 = 2401\) (which is less than 2486)
- \(50^2 = 2500\) (which is greater than 2486)

### Step 4: Calculate the difference
Since we want to subtract from 2486 to reach the nearest perfect square, we will subtract 2401 from 2486:

\[ 2486 - 2401 = 85 \]

### Conclusion
The least number to be subtracted from 2486 to make it a perfect square is:

\[ \boxed{85} \]