OK, let's do this. We've got 6349 and 2417 and we're adding them all together.

Step 1: We'll start by adding the digits 9 & 7 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 4 & 1 in column 2 and get 6.

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

Step 4: We'll start by adding the digits 6 & 2 in column 4 and get 8.

So, 6349 + 2417 = 8766.

