Not to worry, we've got 8445 and 1400. Let's get to adding them!

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 4 & 4 in column 3 and get 8.

Step 4: We'll start by adding the digits 8 & 1 in column 4 and get 9.

So, 8445 + 1400 = 9845.

