We are presented with 5099 and 1263. Let's work out the sum.

Step 1: We'll start by adding the digits 9 & 3 in column 1 and get 12.
We'll write down the last digit 2 and carry the 1 to the next column.

Step 2: We'll start by adding the digits 9 & 6 in column 2 and get 16.
We'll write down the last digit 6 and carry the 1 to the next column.

Step 3: We'll start by adding the digits 0 & 2 in column 3 and get 3.

Step 4: We'll start by adding the digits 5 & 1 in column 4 and get 6.

So, 5099 + 1263 = 6362.

