We are presented with 2011 and 2170. Let's work out the sum.

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

Step 2: We'll start by adding the digits 1 & 7 in column 2 and get 8.

Step 3: We'll start by adding the digits 0 & 1 in column 3 and get 1.

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

So, 2011 + 2170 = 4181.

