Here we go! We're going to add 4521 and 3333 together.

Step 1: We'll start by adding the digits 1 & 3 in column 1 and get 4.

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

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

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

So, 4521 + 3333 = 7854.

