To quickly square a 3-digit number with a 0 in the center is very easy. For example, number such as 203, 504, etc.), you can follow this short trick.

Steps:

- Square the first digit (a) and place it in the ten-thousands place.
- Square the last digit (b) and place it in the units place.
- Multiply the first and last digits (a and b), double the result, and place it in the hundreds place.

Example 1: 2003^2

- Square of 2: 2^2 = 4→ 40000.
- Square of 3: 3^2 = 9→ 9.
- Multiply 2 and 3, double it: , then 2 x 3 = 6, then 6 x 2 = 12→ 1200.

Now, add them up:

203^2 = 40000 + 1200 + 9 = 41,209