We have numbers 6407 and 3289. Let's start adding them together.

Step 1: We'll start by adding the digits 7 & 9 in column 1 and get 16.
We'll write down the last digit 6 and carry the 1 to the next column.

Step 2: We'll start by adding the digits 0 & 8 in column 2 and get 9.

Step 3: We'll start by adding the digits 4 & 2 in column 3 and get 6.

Step 4: We'll start by adding the digits 6 & 3 in column 4 and get 9.

So, 6407 + 3289 = 9696.

