We look at the division of 15649881 by 685 
The aim is to understand the frequency of 685 in 15649881.

On to step 1:
If we divide 1 by 685, we get 0 and a remainder of 1.
Write down 0 as next digit of the result. 
Result so far: 0.0
If we take 0 away from 1, we end up with 1.
Bring next digit (5) of the dividend behind the 1 and repeat the process: 15 / 685

Step 2:
When dividing 15 by 685, we get 0 with a remainder of 15.
The next digit of our result is 0. 
Result so far: 0.0
Deduct 0 from 15 and we're left with 15.
Fetch the next digit (6) from the dividend, attach it to 15 and continue: 156 / 685

On to step 3:
If we divide 156 by 685, we get 0 and a remainder of 156.
Write down 0 as next digit of the result. 
Result so far: 0.0
Subtracting 0 from 156 leaves us with 156.
Take the next digit (4) from the dividend and append it to 156, then repeat: 1564 / 685

Advancing to step 4:
685 goes into 1564 2 times with a remainder of 194.
Put 2 as the next digit of the answer. 
Result so far: 2.0
Subtracting 1370 from 1564 leaves us with 194.
Append the next digit (9) from the dividend to 194 and continue with: 1949 / 685

Advancing to step 5:
When dividing 1949 by 685, we get 2 with a remainder of 579.
Use 2 as the next digit of our solution. 
Result so far: 22.0
Deduct 1370 from 1949 and we're left with 579.
Bring next digit (8) of the dividend behind the 579 and repeat the process: 5798 / 685

Moving on to step 6:
When dividing 5798 by 685, we get 8 with a remainder of 318.
Use 8 as the next digit of our solution. 
Result so far: 228.0
Deduct 5480 from 5798 and we're left with 318.
Take the next digit (8) from the dividend and append it to 318, then repeat: 3188 / 685

Advancing to step 7:
685 goes into 3188 4 times with a remainder of 448.
Use 4 as the next digit of our solution. 
Result so far: 2284.0
The remainder is 448 after subtracting 2740 from 3188.
Append the next digit (1) from the dividend to 448 and continue with: 4481 / 685

Moving on to step 8:
685 can be fit into 4481 6 times, resulting in a remainder of 371.
Write down 6 as next digit of the result. 
Result so far: 22846.0
Subtracting 4110 from 4481 leaves us with 371.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3710, and continue the process.

Going ahead to step 9:
The number 685 fits into 3710 5 times, leaving a remainder of 285.
Use 5 as the next digit of our solution. 
Result so far: 22846.5
Deduct 3425 from 3710 and we're left with 285.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2850, and continue the process.

Step 10:
685 goes into 2850 4 times with a remainder of 110.
The next digit of our result is 4. 
Result so far: 22846.54
If we take 2740 away from 2850, we end up with 110.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1100, and continue the process.

Step 11:
685 goes into 1100 1 times with a remainder of 415.
Put 1 as the next digit of the answer. 
Result so far: 22846.541
If we take 685 away from 1100, we end up with 415.
Since there are no more digits in the dividend, we add a zero to the remainder making it 4150, and continue the process.

On to step 12:
685 goes into 4150 6 times with a remainder of 40.
The number 6 becomes the next digit in our result. 
Result so far: 22846.5416
If we take 4110 away from 4150, we end up with 40.
Since there are no more digits in the dividend, we add a zero to the remainder making it 400, and continue the process.

Let's proceed to step 13:
When dividing 400 by 685, we get 0 with a remainder of 400.
Record the quotient 0 as the next digit in the result. 
Result so far: 22846.5416
Subtracting 0 from 400 leaves us with 400.
Since there are no more digits in the dividend, we add a zero to the remainder making it 4000, and continue the process.

Step 14:
The number 685 fits into 4000 5 times, leaving a remainder of 575.
Use 5 as the next digit of our solution. 
Result so far: 22846.541605
If we take 3425 away from 4000, we end up with 575.
Since there are no more digits in the dividend, we add a zero to the remainder making it 5750, and continue the process.

On to step 15:
685 can be fit into 5750 8 times, resulting in a remainder of 270.
Put 8 as the next digit of the answer. 
Result so far: 22846.5416058
The remainder is 270 after subtracting 5480 from 5750.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2700, and continue the process.

Going ahead to step 16:
2700 divided by 685 is 3 with a remainder of 645.
Record the quotient 3 as the next digit in the result. 
Result so far: 22846.54160583
Deduct 2055 from 2700 and we're left with 645.
Since there are no more digits in the dividend, we add a zero to the remainder making it 6450, and continue the process.

Our division results in 22846.54160583 with a remaining 6.45e-07.