We've got two numbers: 3512 and 5346. Let's find their sum.

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

Step 2: We'll start by adding the digits 1 & 4 in column 2 and get 5.

Step 3: We'll start by adding the digits 5 & 3 in column 3 and get 8.

Step 4: We'll start by adding the digits 3 & 5 in column 4 and get 8.

So, 3512 + 5346 = 8858.

