Ready to do some math? We're starting with 45 and 9954 and adding them up.

Step 1: We'll start by adding the digits 5 & 4 in column 1 and get 9.

Step 2: We'll start by adding the digits 4 & 5 in column 2 and get 9.

Step 3: We'll start by adding the digits 0 & 9 in column 3 and get 9.

Step 4: We'll start by adding the digits 0 & 9 in column 4 and get 9.

So, 45 + 9954 = 9999.

