13880359 ÷ 831 
The aim is to understand the frequency of 831 in 13880359.

Step 1:
When dividing 1 by 831, we get 0 with a remainder of 1.
Use 0 as the next digit of our solution. 
Result so far: 0.0
Subtracting 0 from 1 leaves us with 1.
Append the next digit (3) from the dividend to 1 and continue with: 13 / 831

Going ahead to step 2:
The number 831 fits into 13 0 times, leaving a remainder of 13.
Use 0 as the next digit of our solution. 
Result so far: 0.0
Subtract 0 from 13 to get 13.
Include the next digit (8) from the dividend after 13, then repeat: 138 / 831

On to step 3:
138 divided by 831 is 0 with a remainder of 138.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
The remainder is 138 after subtracting 0 from 138.
Take the next digit (8) from the dividend and append it to 138, then repeat: 1388 / 831

Step 4:
831 can be fit into 1388 1 times, resulting in a remainder of 557.
The number 1 becomes the next digit in our result. 
Result so far: 1.0
Subtracting 831 from 1388 leaves us with 557.
Take the next digit (0) from the dividend and append it to 557, then repeat: 5570 / 831

Moving on to step 5:
The number 831 fits into 5570 6 times, leaving a remainder of 584.
Put 6 as the next digit of the answer. 
Result so far: 16.0
If we take 4986 away from 5570, we end up with 584.
Fetch the next digit (3) from the dividend, attach it to 584 and continue: 5843 / 831

On to step 6:
If we divide 5843 by 831, we get 7 and a remainder of 26.
Record the quotient 7 as the next digit in the result. 
Result so far: 167.0
If we take 5817 away from 5843, we end up with 26.
Append the next digit (5) from the dividend to 26 and continue with: 265 / 831

Step 7:
831 can be fit into 265 0 times, resulting in a remainder of 265.
Put 0 as the next digit of the answer. 
Result so far: 1670.0
If we take 0 away from 265, we end up with 265.
Include the next digit (9) from the dividend after 265, then repeat: 2659 / 831

Let's proceed to step 8:
831 goes into 2659 3 times with a remainder of 166.
The number 3 becomes the next digit in our result. 
Result so far: 16703.0
If we take 2493 away from 2659, we end up with 166.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1660, and continue the process.

On to step 9:
831 can be fit into 1660 1 times, resulting in a remainder of 829.
The number 1 becomes the next digit in our result. 
Result so far: 16703.1
The remainder is 829 after subtracting 831 from 1660.
Since there are no more digits in the dividend, we add a zero to the remainder making it 8290, and continue the process.

Going ahead to step 10:
8290 divided by 831 is 9 with a remainder of 811.
The next digit of our result is 9. 
Result so far: 16703.19
If we subtract 7479 from 8290, we get 811.
Since there are no more digits in the dividend, we add a zero to the remainder making it 8110, and continue the process.

Let's proceed to step 11:
831 goes into 8110 9 times with a remainder of 631.
Record the quotient 9 as the next digit in the result. 
Result so far: 16703.199
Deduct 7479 from 8110 and we're left with 631.
Since there are no more digits in the dividend, we add a zero to the remainder making it 6310, and continue the process.

The final result is 16703.199 with a remainder of 0.0631.