Let's get this math done. We have 3402 and 6447 and we're going to add them all together.

Step 1: We'll start by adding the digits 2 & 7 in column 1 and get 9.

Step 2: We'll start by adding the digits 0 & 4 in column 2 and get 4.

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

Step 4: We'll start by adding the digits 3 & 6 in column 4 and get 9.

So, 3402 + 6447 = 9849.

