Here we go! We're going to add 6435 and 8351 together.

Step 1: We'll start by adding the digits 5 & 1 in column 1 and get 6.

Step 2: We'll start by adding the digits 3 & 5 in column 2 and get 8.

Step 3: We'll start by adding the digits 4 & 3 in column 3 and get 7.

Step 4: We'll start by adding the digits 6 & 8 in column 4 and get 14.
We'll write down the last digit 4 and carry the 1 to the next column.

So, 6435 + 8351 = 14786.

