We are presented with 7591 and 5201. Let's work out the sum.

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

Step 2: We'll start by adding the digits 9 & 0 in column 2 and get 9.

Step 3: We'll start by adding the digits 5 & 2 in column 3 and get 7.

Step 4: We'll start by adding the digits 7 & 5 in column 4 and get 12.
We'll write down the last digit 2 and carry the 1 to the next column.

So, 7591 + 5201 = 12792.

