Here we go! We're going to add 7770 and 7090 together.

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 & 9 in column 2 and get 16.
We'll write down the last digit 6 and carry the 1 to the next column.

Step 3: We'll start by adding the digits 7 & 0 in column 3 and get 8.

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

So, 7770 + 7090 = 14860.

