503178 divided by 12 
The aim is to understand the frequency of 12 in 503178.

Step 1:
When dividing 5 by 12, we get 0 with a remainder of 5.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
The remainder is 5 after subtracting 0 from 5.
Append the next digit (0) from the dividend to 5 and continue with: 50 / 12

Advancing to step 2:
12 goes into 50 4 times with a remainder of 2.
Write down 4 as next digit of the result. 
Result so far: 4.0
If we subtract 48 from 50, we get 2.
Grab the next digit (3) from the dividend, add it to 2, then carry on: 23 / 12

Advancing to step 3:
12 goes into 23 1 times with a remainder of 11.
The next digit of our result is 1. 
Result so far: 41.0
Subtracting 12 from 23 leaves us with 11.
Fetch the next digit (1) from the dividend, attach it to 11 and continue: 111 / 12

Let's proceed to step 4:
111 divided by 12 is 9 with a remainder of 3.
Record the quotient 9 as the next digit in the result. 
Result so far: 419.0
Deduct 108 from 111 and we're left with 3.
Grab the next digit (7) from the dividend, add it to 3, then carry on: 37 / 12

Moving on to step 5:
12 can be fit into 37 3 times, resulting in a remainder of 1.
Put 3 as the next digit of the answer. 
Result so far: 4193.0
If we take 36 away from 37, we end up with 1.
Append the next digit (8) from the dividend to 1 and continue with: 18 / 12

Advancing to step 6:
18 divided by 12 is 1 with a remainder of 6.
Use 1 as the next digit of our solution. 
Result so far: 41931.0
The remainder is 6 after subtracting 12 from 18.
Since there are no more digits in the dividend, we add a zero to the remainder making it 60, and continue the process.

Step 7:
The number 12 fits into 60 5 times, leaving a remainder of 0.
Record the quotient 5 as the next digit in the result. 
Result so far: 41931.5
If we subtract 60 from 60, we get 0.
Since there are no more digits in the dividend, we add a zero to the remainder making it 0, and continue the process.

Step 8:
12 goes into 0 0 times with a remainder of 0.
Write down 0 as next digit of the result. 
Result so far: 41931.5
The remainder is 0 after subtracting 0 from 0.
Since there are no more digits in the dividend, we add a zero to the remainder making it 0, and continue the process.

Advancing to step 9:
12 can be fit into 0 0 times, resulting in a remainder of 0.
The number 0 becomes the next digit in our result. 
Result so far: 41931.5
Subtracting 0 from 0 leaves us with 0.
Since there are no more digits in the dividend, we add a zero to the remainder making it 0, and continue the process.

The final result is 41931.5 with a remainder of 0.0.