Okay, we are given 1270 and 6600. Let's add them up step by step.

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

Step 2: We'll start by adding the digits 7 & 0 in column 2 and get 7.

Step 3: We'll start by adding the digits 2 & 6 in column 3 and get 8.

Step 4: We'll start by adding the digits 1 & 6 in column 4 and get 7.

So, 1270 + 6600 = 7870.

