OK, let's do this. We've got 1400 and 6302 and we're adding them all together.

Step 1: We'll start by adding the digits 0 & 2 in column 1 and get 2.

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

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 1 & 6 in column 4 and get 7.

So, 1400 + 6302 = 7702.

