OK, let's do this. We've got 1644 and 3124 and we're adding them all together.

Step 1: We'll start by adding the digits 4 & 4 in column 1 and get 8.

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

Step 3: We'll start by adding the digits 6 & 1 in column 3 and get 7.

Step 4: We'll start by adding the digits 1 & 3 in column 4 and get 4.

So, 1644 + 3124 = 4768.

