Got it! So, we have 78439440 and 27571356, and we'll subtract the latter from the former.

Step 1: We'll start by subtracting the digit 6 and the borrow 0 from 0 in column 1 and get -6.
We add -6 to 10 and get 4 as the first digit of the result.

Step 2: We'll start by subtracting the digit 5 and the borrow 1 from 4 in column 2 and get -2.
We add -2 to 10 and get 8 as the next digit of the result.

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

Step 4: We'll start by subtracting the digit 1 and the borrow 0 from 9 in column 4 and get 8.
8 is the next digit of our result.

Step 5: We'll start by subtracting the digit 7 and the borrow 0 from 3 in column 5 and get -4.
We add -4 to 10 and get 6 as the next digit of the result.

Step 6: We'll start by subtracting the digit 5 and the borrow 1 from 4 in column 6 and get -2.
We add -2 to 10 and get 8 as the next digit of the result.

Step 7: We'll start by subtracting the digit 7 and the borrow 1 from 8 in column 7 and get 0.
0 is the next digit of our result.

Step 8: We'll start by subtracting the digit 2 and the borrow 0 from 7 in column 8 and get 5.
5 is the next digit of our result.

So, 78439440 - 27571356 = 50868084.