OK, let's do this. We've got 4245 and 1300 and we're adding them all together.

Step 1: We'll start by adding the digits 5 & 0 in column 1 and get 5.

Step 2: We'll start by adding the digits 4 & 0 in column 2 and get 4.

Step 3: We'll start by adding the digits 2 & 3 in column 3 and get 5.

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

So, 4245 + 1300 = 5545.

