Here we go! We're going to add 2102 and 7535 together.

Step 1: We'll start by adding the digits 2 & 5 in column 1 and get 7.

Step 2: We'll start by adding the digits 0 & 3 in column 2 and get 3.

Step 3: We'll start by adding the digits 1 & 5 in column 3 and get 6.

Step 4: We'll start by adding the digits 2 & 7 in column 4 and get 9.

So, 2102 + 7535 = 9637.

