Okay, let's tackle this math problem. We're starting with 72463 and subtracting 51131.

Step 1: We'll start by subtracting the digit 1 and the borrow 0 from 3 in column 1 and get 2.
2 is the first digit of our result.

Step 2: We'll start by subtracting the digit 3 and the borrow 0 from 6 in column 2 and get 3.
3 is the next digit of our result.

Step 3: We'll start by subtracting the digit 1 and the borrow 0 from 4 in column 3 and get 3.
3 is the next digit of our result.

Step 4: We'll start by subtracting the digit 1 and the borrow 0 from 2 in column 4 and get 1.
1 is the next digit of our result.

Step 5: We'll start by subtracting the digit 5 and the borrow 0 from 7 in column 5 and get 2.
2 is the next digit of our result.

So, 72463 - 51131 = 21332.