We are presented with 8422 and 1279. Let's work out the sum.

Step 1: We'll start by adding the digits 2 & 9 in column 1 and get 11.
We'll write down the last digit 1 and carry the 1 to the next column.

Step 2: We'll start by adding the digits 2 & 7 in column 2 and get 10.
We'll write down the last digit 0 and carry the 1 to the next column.

Step 3: We'll start by adding the digits 4 & 2 in column 3 and get 7.

Step 4: We'll start by adding the digits 8 & 1 in column 4 and get 9.

So, 8422 + 1279 = 9701.

