We look at the division of 15917043 by 12 
The aim is to understand the frequency of 12 in 15917043.

Let's proceed to step 1:
When dividing 1 by 12, we get 0 with a remainder of 1.
Put 0 as the next digit of the answer. 
Result so far: 0.0
If we take 0 away from 1, we end up with 1.
Append the next digit (5) from the dividend to 1 and continue with: 15 / 12

Step 2:
12 can be fit into 15 1 times, resulting in a remainder of 3.
The number 1 becomes the next digit in our result. 
Result so far: 1.0
The remainder is 3 after subtracting 12 from 15.
Take the next digit (9) from the dividend and append it to 3, then repeat: 39 / 12

Let's proceed to step 3:
12 goes into 39 3 times with a remainder of 3.
The next digit of our result is 3. 
Result so far: 13.0
The remainder is 3 after subtracting 36 from 39.
Bring next digit (1) of the dividend behind the 3 and repeat the process: 31 / 12

Let's proceed to step 4:
31 divided by 12 is 2 with a remainder of 7.
Put 2 as the next digit of the answer. 
Result so far: 132.0
If we subtract 24 from 31, we get 7.
Fetch the next digit (7) from the dividend, attach it to 7 and continue: 77 / 12

Let's proceed to step 5:
When dividing 77 by 12, we get 6 with a remainder of 5.
Write down 6 as next digit of the result. 
Result so far: 1326.0
Deduct 72 from 77 and we're left with 5.
Include the next digit (0) from the dividend after 5, then repeat: 50 / 12

Going ahead to step 6:
When dividing 50 by 12, we get 4 with a remainder of 2.
Use 4 as the next digit of our solution. 
Result so far: 13264.0
If we take 48 away from 50, we end up with 2.
Append the next digit (4) from the dividend to 2 and continue with: 24 / 12

Let's proceed to step 7:
12 goes into 24 2 times with a remainder of 0.
Use 2 as the next digit of our solution. 
Result so far: 132642.0
If we subtract 24 from 24, we get 0.
Include the next digit (3) from the dividend after 0, then repeat: 3 / 12

Going ahead to step 8:
When dividing 3 by 12, we get 0 with a remainder of 3.
Put 0 as the next digit of the answer. 
Result so far: 1326420.0
If we subtract 0 from 3, we get 3.
Since there are no more digits in the dividend, we add a zero to the remainder making it 30, and continue the process.

Let's proceed to step 9:
When dividing 30 by 12, we get 2 with a remainder of 6.
The number 2 becomes the next digit in our result. 
Result so far: 1326420.2
Subtract 24 from 30 to get 6.
Since there are no more digits in the dividend, we add a zero to the remainder making it 60, and continue the process.

Advancing to step 10:
12 goes into 60 5 times with a remainder of 0.
Put 5 as the next digit of the answer. 
Result so far: 1326420.25
The remainder is 0 after subtracting 60 from 60.
Since there are no more digits in the dividend, we add a zero to the remainder making it 0, and continue the process.

Let's proceed to step 11:
12 goes into 0 0 times with a remainder of 0.
Record the quotient 0 as the next digit in the result. 
Result so far: 1326420.25
If we take 0 away from 0, we end up 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.

Let's proceed to step 12:
The number 12 fits into 0 0 times, leaving a remainder of 0.
Record the quotient 0 as the next digit in the result. 
Result so far: 1326420.25
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 1326420.25 with a remainder of 0.0.