Let's get this math done. We have 2215 and 2121 and we're going to add them all together.

Step 1: We'll start by adding the digits 5 & 1 in column 1 and get 6.

Step 2: We'll start by adding the digits 1 & 2 in column 2 and get 3.

Step 3: We'll start by adding the digits 2 & 1 in column 3 and get 3.

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

So, 2215 + 2121 = 4336.

