Let's get this math done. We have 7231 and 2115 and we're going to add them all together.

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

Step 2: We'll start by adding the digits 3 & 1 in column 2 and get 4.

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 7 & 2 in column 4 and get 9.

So, 7231 + 2115 = 9346.

