We're dividing 578215 by 91 
The aim is to understand the frequency of 91 in 578215.

Moving on to step 1:
91 goes into 5 0 times with a remainder of 5.
Use 0 as the next digit of our solution. 
Result so far: 0.0
Subtract 0 from 5 to get 5.
Include the next digit (7) from the dividend after 5, then repeat: 57 / 91

On to step 2:
91 goes into 57 0 times with a remainder of 57.
Write down 0 as next digit of the result. 
Result so far: 0.0
Subtract 0 from 57 to get 57.
Fetch the next digit (8) from the dividend, attach it to 57 and continue: 578 / 91

On to step 3:
578 divided by 91 is 6 with a remainder of 32.
The next digit of our result is 6. 
Result so far: 6.0
Subtracting 546 from 578 leaves us with 32.
Grab the next digit (2) from the dividend, add it to 32, then carry on: 322 / 91

Step 4:
91 can be fit into 322 3 times, resulting in a remainder of 49.
Put 3 as the next digit of the answer. 
Result so far: 63.0
Deduct 273 from 322 and we're left with 49.
Bring next digit (1) of the dividend behind the 49 and repeat the process: 491 / 91

Advancing to step 5:
91 can be fit into 491 5 times, resulting in a remainder of 36.
Use 5 as the next digit of our solution. 
Result so far: 635.0
Subtracting 455 from 491 leaves us with 36.
Fetch the next digit (5) from the dividend, attach it to 36 and continue: 365 / 91

Let's proceed to step 6:
If we divide 365 by 91, we get 4 and a remainder of 1.
Record the quotient 4 as the next digit in the result. 
Result so far: 6354.0
If we take 364 away from 365, we end up 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.

Advancing to step 7:
When dividing 10 by 91, we get 0 with a remainder of 10.
Use 0 as the next digit of our solution. 
Result so far: 6354.0
If we take 0 away from 10, we end up 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.

Let's proceed to step 8:
91 goes into 100 1 times with a remainder of 9.
The next digit of our result is 1. 
Result so far: 6354.01
Deduct 91 from 100 and we're left with 9.
Since there are no more digits in the dividend, we add a zero to the remainder making it 90, and continue the process.

Moving on to step 9:
91 goes into 90 0 times with a remainder of 90.
Write down 0 as next digit of the result. 
Result so far: 6354.01
If we subtract 0 from 90, we 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.

On to step 10:
The number 91 fits into 900 9 times, leaving a remainder of 81.
The number 9 becomes the next digit in our result. 
Result so far: 6354.0109
Subtracting 819 from 900 leaves us with 81.
Since there are no more digits in the dividend, we add a zero to the remainder making it 810, and continue the process.

Let's proceed to step 11:
91 can be fit into 810 8 times, resulting in a remainder of 82.
Put 8 as the next digit of the answer. 
Result so far: 6354.01098
Subtracting 728 from 810 leaves us with 82.
Since there are no more digits in the dividend, we add a zero to the remainder making it 820, and continue the process.

Going ahead to step 12:
If we divide 820 by 91, we get 9 and a remainder of 1.
The number 9 becomes the next digit in our result. 
Result so far: 6354.010989
If we take 819 away from 820, we end up 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.

Let's proceed to step 13:
10 divided by 91 is 0 with a remainder of 10.
Put 0 as the next digit of the answer. 
Result so far: 6354.010989
If we subtract 0 from 10, we get 10.
Since there are no more digits in the dividend, we add a zero to the remainder making it 100, and continue the process.

Step 14:
When dividing 100 by 91, we get 1 with a remainder of 9.
Use 1 as the next digit of our solution. 
Result so far: 6354.01098901
If we subtract 91 from 100, we 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.

After the division, we end up with 6354.01098901 and a remainder of 9e-09.