We are presented with 9725 and 210. Let's work out the sum.

Step 1: We'll start by adding the digits 5 & 0 in column 1 and get 5.

Step 2: We'll start by adding the digits 2 & 1 in column 2 and get 3.

Step 3: We'll start by adding the digits 7 & 2 in column 3 and get 9.

Step 4: We'll start by adding the digits 9 & 0 in column 4 and get 9.

So, 9725 + 210 = 9935.

