How to add four digit numbers (for example 4529 + 6733):

• Place one number above the other so that the thousands', hundreds', tens' and ones' places are lined up. Draw a line under the bottom number.

4529
6733

• Add the ones' place digits (9 + 3 = 12). This number is larger than 10 so place a one above the tens' place column and place the two below the line in the ones' place column.

  1
4529
6733
   2

• Add the tens' place digits (1 + 2 + 3 = 6) and place the answer below the line and in the tens' place column.

4529
6733
  62

• Add the numbers in the hundreds' place column (5 + 7 = 12) and place the 2 below the line and before the other number below the line. Place the 1 from the twelve above the thousands' place column.

1
4529
6733
 262

• Add the digits in the thousands' place column (1 + 4 + 6 = 11) and place the answer below the line in the thousands' place column.

 4529
 6733
11262