579371 divided by 91 
The aim is to understand the frequency of 91 in 579371.

Step 1:
5 divided by 91 is 0 with a remainder of 5.
Use 0 as the next digit of our solution. 
Result so far: 0.0
If we take 0 away from 5, we end up with 5.
Fetch the next digit (7) from the dividend, attach it to 5 and continue: 57 / 91

Advancing to step 2:
If we divide 57 by 91, we get 0 and 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.
Append the next digit (9) from the dividend to 57 and continue with: 579 / 91

Going ahead to step 3:
When dividing 579 by 91, we get 6 with a remainder of 33.
Use 6 as the next digit of our solution. 
Result so far: 6.0
Deduct 546 from 579 and we're left with 33.
Fetch the next digit (3) from the dividend, attach it to 33 and continue: 333 / 91

Moving on to step 4:
The number 91 fits into 333 3 times, leaving a remainder of 60.
Use 3 as the next digit of our solution. 
Result so far: 63.0
If we subtract 273 from 333, we get 60.
Fetch the next digit (7) from the dividend, attach it to 60 and continue: 607 / 91

Let's proceed to step 5:
If we divide 607 by 91, we get 6 and a remainder of 61.
Use 6 as the next digit of our solution. 
Result so far: 636.0
Subtracting 546 from 607 leaves us with 61.
Grab the next digit (1) from the dividend, add it to 61, then carry on: 611 / 91

Let's proceed to step 6:
The number 91 fits into 611 6 times, leaving a remainder of 65.
Put 6 as the next digit of the answer. 
Result so far: 6366.0
Deduct 546 from 611 and we're left with 65.
Since there are no more digits in the dividend, we add a zero to the remainder making it 650, and continue the process.

Step 7:
91 can be fit into 650 7 times, resulting in a remainder of 13.
Record the quotient 7 as the next digit in the result. 
Result so far: 6366.7
The remainder is 13 after subtracting 637 from 650.
Since there are no more digits in the dividend, we add a zero to the remainder making it 130, and continue the process.

Let's proceed to step 8:
91 can be fit into 130 1 times, resulting in a remainder of 39.
The next digit of our result is 1. 
Result so far: 6366.71
If we subtract 91 from 130, we get 39.
Since there are no more digits in the dividend, we add a zero to the remainder making it 390, and continue the process.

Moving on to step 9:
When dividing 390 by 91, we get 4 with a remainder of 26.
Record the quotient 4 as the next digit in the result. 
Result so far: 6366.714
The remainder is 26 after subtracting 364 from 390.
Since there are no more digits in the dividend, we add a zero to the remainder making it 260, and continue the process.

Advancing to step 10:
If we divide 260 by 91, we get 2 and a remainder of 78.
The number 2 becomes the next digit in our result. 
Result so far: 6366.7142
Subtracting 182 from 260 leaves us with 78.
Since there are no more digits in the dividend, we add a zero to the remainder making it 780, and continue the process.

Step 11:
The number 91 fits into 780 8 times, leaving a remainder of 52.
Use 8 as the next digit of our solution. 
Result so far: 6366.71428
If we subtract 728 from 780, we get 52.
Since there are no more digits in the dividend, we add a zero to the remainder making it 520, and continue the process.

Step 12:
When dividing 520 by 91, we get 5 with a remainder of 65.
Record the quotient 5 as the next digit in the result. 
Result so far: 6366.714285
Deduct 455 from 520 and we're left with 65.
Since there are no more digits in the dividend, we add a zero to the remainder making it 650, and continue the process.

Advancing to step 13:
If we divide 650 by 91, we get 7 and a remainder of 13.
Put 7 as the next digit of the answer. 
Result so far: 6366.7142857
Deduct 637 from 650 and we're left with 13.
Since there are no more digits in the dividend, we add a zero to the remainder making it 130, and continue the process.

On to step 14:
130 divided by 91 is 1 with a remainder of 39.
The number 1 becomes the next digit in our result. 
Result so far: 6366.71428571
Deduct 91 from 130 and we're left with 39.
Since there are no more digits in the dividend, we add a zero to the remainder making it 390, and continue the process.

The final result is 6366.71428571 with a remainder of 3.9e-08.