Multiplying Two digit Numbers With difference of 3

1. Choose a 2-digit number.
2. Select a number either 3 smaller or 3 larger.
3. Add 1 to the smaller number, then square.
4. Subtract one from the smaller number.
5. Add this to the square.

Example:

1. If the first number is 27, choose 24 as the second number.
2. Add 1 to the smaller number: 24 + 1 = 25.
3. Square this number: 25 × 25 = 625.
4. Subtract one from the smaller number: 24 - 1 = 23.
5. Add this to the square: 625 + 23 = 648.
6. So 27 × 24 = 648.