Here we go! We're going to add 9870 and 6077 together.

Step 1: We'll start by adding the digits 0 & 7 in column 1 and get 7.

Step 2: We'll start by adding the digits 7 & 7 in column 2 and get 14.
We'll write down the last digit 4 and carry the 1 to the next column.

Step 3: We'll start by adding the digits 8 & 0 in column 3 and get 9.

Step 4: We'll start by adding the digits 9 & 6 in column 4 and get 15.
We'll write down the last digit 5 and carry the 1 to the next column.

So, 9870 + 6077 = 15947.

