We look at the division of 85519364 by 391 
The aim is to understand the frequency of 391 in 85519364.

Let's proceed to step 1:
8 divided by 391 is 0 with a remainder of 8.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
If we subtract 0 from 8, we get 8.
Bring next digit (5) of the dividend behind the 8 and repeat the process: 85 / 391

Going ahead to step 2:
85 divided by 391 is 0 with a remainder of 85.
Put 0 as the next digit of the answer. 
Result so far: 0.0
Subtracting 0 from 85 leaves us with 85.
Append the next digit (5) from the dividend to 85 and continue with: 855 / 391

Advancing to step 3:
391 goes into 855 2 times with a remainder of 73.
The next digit of our result is 2. 
Result so far: 2.0
Subtracting 782 from 855 leaves us with 73.
Include the next digit (1) from the dividend after 73, then repeat: 731 / 391

On to step 4:
391 can be fit into 731 1 times, resulting in a remainder of 340.
Write down 1 as next digit of the result. 
Result so far: 21.0
If we subtract 391 from 731, we get 340.
Fetch the next digit (9) from the dividend, attach it to 340 and continue: 3409 / 391

Going ahead to step 5:
391 can be fit into 3409 8 times, resulting in a remainder of 281.
The next digit of our result is 8. 
Result so far: 218.0
The remainder is 281 after subtracting 3128 from 3409.
Include the next digit (3) from the dividend after 281, then repeat: 2813 / 391

Step 6:
2813 divided by 391 is 7 with a remainder of 76.
The next digit of our result is 7. 
Result so far: 2187.0
Deduct 2737 from 2813 and we're left with 76.
Append the next digit (6) from the dividend to 76 and continue with: 766 / 391

Moving on to step 7:
391 goes into 766 1 times with a remainder of 375.
The number 1 becomes the next digit in our result. 
Result so far: 21871.0
The remainder is 375 after subtracting 391 from 766.
Include the next digit (4) from the dividend after 375, then repeat: 3754 / 391

Let's proceed to step 8:
391 goes into 3754 9 times with a remainder of 235.
The next digit of our result is 9. 
Result so far: 218719.0
The remainder is 235 after subtracting 3519 from 3754.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2350, and continue the process.

Step 9:
If we divide 2350 by 391, we get 6 and a remainder of 4.
The number 6 becomes the next digit in our result. 
Result so far: 218719.6
If we take 2346 away from 2350, we end up with 4.
Since there are no more digits in the dividend, we add a zero to the remainder making it 40, and continue the process.

Moving on to step 10:
40 divided by 391 is 0 with a remainder of 40.
The number 0 becomes the next digit in our result. 
Result so far: 218719.6
If we take 0 away from 40, 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.

Moving on to step 11:
391 can be fit into 400 1 times, resulting in a remainder of 9.
The number 1 becomes the next digit in our result. 
Result so far: 218719.601
Subtract 391 from 400 to get 9.
Since there are no more digits in the dividend, we add a zero to the remainder making it 90, and continue the process.

Step 12:
If we divide 90 by 391, we get 0 and a remainder of 90.
The number 0 becomes the next digit in our result. 
Result so far: 218719.601
Subtract 0 from 90 to get 90.
Since there are no more digits in the dividend, we add a zero to the remainder making it 900, and continue the process.

Let's proceed to step 13:
The number 391 fits into 900 2 times, leaving a remainder of 118.
Put 2 as the next digit of the answer. 
Result so far: 218719.60102
If we subtract 782 from 900, we get 118.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1180, and continue the process.

Going ahead to step 14:
The number 391 fits into 1180 3 times, leaving a remainder of 7.
Use 3 as the next digit of our solution. 
Result so far: 218719.601023
Subtracting 1173 from 1180 leaves us with 7.
Since there are no more digits in the dividend, we add a zero to the remainder making it 70, and continue the process.

Step 15:
391 goes into 70 0 times with a remainder of 70.
The number 0 becomes the next digit in our result. 
Result so far: 218719.601023
If we take 0 away from 70, we end up with 70.
Since there are no more digits in the dividend, we add a zero to the remainder making it 700, and continue the process.

Let's proceed to step 16:
If we divide 700 by 391, we get 1 and a remainder of 309.
The number 1 becomes the next digit in our result. 
Result so far: 218719.60102301
The remainder is 309 after subtracting 391 from 700.
Since there are no more digits in the dividend, we add a zero to the remainder making it 3090, and continue the process.

The final outcome is 218719.60102301, with a leftover of 3.09e-07.