OK, let's do this. We've got 400 and 5250 and we're adding them all together.

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

Step 2: We'll start by adding the digits 0 & 5 in column 2 and get 5.

Step 3: We'll start by adding the digits 4 & 2 in column 3 and get 6.

Step 4: We'll start by adding the digits 0 & 5 in column 4 and get 5.

So, 400 + 5250 = 5650.

