We have numbers 6409 and 2110. Let's start adding them together.

Step 1: We'll start by adding the digits 9 & 0 in column 1 and get 9.

Step 2: We'll start by adding the digits 0 & 1 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 6 & 2 in column 4 and get 8.

So, 6409 + 2110 = 8519.

