Let's solve this addition problem. We have 7335 and 1524, and we need to add them together.

Step 1: We'll start by adding the digits 5 & 4 in column 1 and get 9.

Step 2: We'll start by adding the digits 3 & 2 in column 2 and get 5.

Step 3: We'll start by adding the digits 3 & 5 in column 3 and get 8.

Step 4: We'll start by adding the digits 7 & 1 in column 4 and get 8.

So, 7335 + 1524 = 8859.

