Okay, we are given 5948 and 2521. Let's add them up step by step.

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

Step 2: We'll start by adding the digits 4 & 2 in column 2 and get 6.

Step 3: We'll start by adding the digits 9 & 5 in column 3 and get 14.
We'll write down the last digit 4 and carry the 1 to the next column.

Step 4: We'll start by adding the digits 5 & 2 in column 4 and get 8.

So, 5948 + 2521 = 8469.

