We've got two numbers: 8494 and 3431. Let's find their sum.

Step 1: We'll start by adding the digits 4 & 1 in column 1 and get 5.

Step 2: We'll start by adding the digits 9 & 3 in column 2 and get 12.
We'll write down the last digit 2 and carry the 1 to the next column.

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

Step 4: We'll start by adding the digits 8 & 3 in column 4 and get 11.
We'll write down the last digit 1 and carry the 1 to the next column.

So, 8494 + 3431 = 11925.

