We are presented with 2161 and 7421. 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 6 & 2 in column 2 and get 8.

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

Step 4: We'll start by adding the digits 2 & 7 in column 4 and get 9.

So, 2161 + 7421 = 9582.

