We are presented with 4405 and 5105. Let's work out the sum.

Step 1: We'll start by adding the digits 5 & 5 in column 1 and get 10.
We'll write down the last digit 0 and carry the 1 to the next column.

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

Step 3: We'll start by adding the digits 4 & 1 in column 3 and get 5.

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

So, 4405 + 5105 = 9510.

