We look at the division of 84020818 by 391 
The aim is to understand the frequency of 391 in 84020818.

Advancing to step 1:
391 goes into 8 0 times with a remainder of 8.
Put 0 as the next digit of the answer. 
Result so far: 0.0
If we subtract 0 from 8, we get 8.
Fetch the next digit (4) from the dividend, attach it to 8 and continue: 84 / 391

Step 2:
84 divided by 391 is 0 with a remainder of 84.
Write down 0 as next digit of the result. 
Result so far: 0.0
If we take 0 away from 84, we end up with 84.
Bring next digit (0) of the dividend behind the 84 and repeat the process: 840 / 391

Step 3:
When dividing 840 by 391, we get 2 with a remainder of 58.
Use 2 as the next digit of our solution. 
Result so far: 2.0
Subtract 782 from 840 to get 58.
Take the next digit (2) from the dividend and append it to 58, then repeat: 582 / 391

Let's proceed to step 4:
If we divide 582 by 391, we get 1 and a remainder of 191.
Put 1 as the next digit of the answer. 
Result so far: 21.0
Subtract 391 from 582 to get 191.
Take the next digit (0) from the dividend and append it to 191, then repeat: 1910 / 391

Advancing to step 5:
391 goes into 1910 4 times with a remainder of 346.
The next digit of our result is 4. 
Result so far: 214.0
Deduct 1564 from 1910 and we're left with 346.
Fetch the next digit (8) from the dividend, attach it to 346 and continue: 3468 / 391

On to step 6:
The number 391 fits into 3468 8 times, leaving a remainder of 340.
Use 8 as the next digit of our solution. 
Result so far: 2148.0
If we subtract 3128 from 3468, we get 340.
Include the next digit (1) from the dividend after 340, then repeat: 3401 / 391

Let's proceed to step 7:
The number 391 fits into 3401 8 times, leaving a remainder of 273.
Write down 8 as next digit of the result. 
Result so far: 21488.0
Subtracting 3128 from 3401 leaves us with 273.
Include the next digit (8) from the dividend after 273, then repeat: 2738 / 391

Moving on to step 8:
391 can be fit into 2738 7 times, resulting in a remainder of 1.
Write down 7 as next digit of the result. 
Result so far: 214887.0
Deduct 2737 from 2738 and we're left with 1.
Since there are no more digits in the dividend, we add a zero to the remainder making it 10, and continue the process.

Going ahead to step 9:
391 can be fit into 10 0 times, resulting in a remainder of 10.
Write down 0 as next digit of the result. 
Result so far: 214887.0
Deduct 0 from 10 and we're left with 10.
Since there are no more digits in the dividend, we add a zero to the remainder making it 100, and continue the process.

Advancing to step 10:
The number 391 fits into 100 0 times, leaving a remainder of 100.
The next digit of our result is 0. 
Result so far: 214887.0
If we subtract 0 from 100, we get 100.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1000, and continue the process.

The final result is 214887.0 with a remainder of 0.1.