We're dividing 628951 by 91 
The aim is to understand the frequency of 91 in 628951.

On to step 1:
6 divided by 91 is 0 with a remainder of 6.
Write down 0 as next digit of the result. 
Result so far: 0.0
Deduct 0 from 6 and we're left with 6.
Fetch the next digit (2) from the dividend, attach it to 6 and continue: 62 / 91

Advancing to step 2:
91 can be fit into 62 0 times, resulting in a remainder of 62.
Use 0 as the next digit of our solution. 
Result so far: 0.0
The remainder is 62 after subtracting 0 from 62.
Append the next digit (8) from the dividend to 62 and continue with: 628 / 91

Going ahead to step 3:
If we divide 628 by 91, we get 6 and a remainder of 82.
The number 6 becomes the next digit in our result. 
Result so far: 6.0
Deduct 546 from 628 and we're left with 82.
Grab the next digit (9) from the dividend, add it to 82, then carry on: 829 / 91

On to step 4:
91 goes into 829 9 times with a remainder of 10.
Record the quotient 9 as the next digit in the result. 
Result so far: 69.0
Subtract 819 from 829 to get 10.
Include the next digit (5) from the dividend after 10, then repeat: 105 / 91

On to step 5:
91 goes into 105 1 times with a remainder of 14.
Put 1 as the next digit of the answer. 
Result so far: 691.0
The remainder is 14 after subtracting 91 from 105.
Append the next digit (1) from the dividend to 14 and continue with: 141 / 91

Step 6:
When dividing 141 by 91, we get 1 with a remainder of 50.
Use 1 as the next digit of our solution. 
Result so far: 6911.0
Subtract 91 from 141 to get 50.
Since there are no more digits in the dividend, we add a zero to the remainder making it 500, and continue the process.

Advancing to step 7:
91 goes into 500 5 times with a remainder of 45.
The number 5 becomes the next digit in our result. 
Result so far: 6911.5
If we subtract 455 from 500, we get 45.
Since there are no more digits in the dividend, we add a zero to the remainder making it 450, and continue the process.

Step 8:
When dividing 450 by 91, we get 4 with a remainder of 86.
The next digit of our result is 4. 
Result so far: 6911.54
If we subtract 364 from 450, we get 86.
Since there are no more digits in the dividend, we add a zero to the remainder making it 860, and continue the process.

Advancing to step 9:
If we divide 860 by 91, we get 9 and a remainder of 41.
The next digit of our result is 9. 
Result so far: 6911.549
If we take 819 away from 860, we end up with 41.
Since there are no more digits in the dividend, we add a zero to the remainder making it 410, and continue the process.

Advancing to step 10:
91 goes into 410 4 times with a remainder of 46.
Record the quotient 4 as the next digit in the result. 
Result so far: 6911.5494
If we subtract 364 from 410, we get 46.
Since there are no more digits in the dividend, we add a zero to the remainder making it 460, and continue the process.

Let's proceed to step 11:
91 goes into 460 5 times with a remainder of 5.
Put 5 as the next digit of the answer. 
Result so far: 6911.54945
Subtract 455 from 460 to get 5.
Since there are no more digits in the dividend, we add a zero to the remainder making it 50, and continue the process.

Going ahead to step 12:
When dividing 50 by 91, we get 0 with a remainder of 50.
The number 0 becomes the next digit in our result. 
Result so far: 6911.54945
Deduct 0 from 50 and we're left with 50.
Since there are no more digits in the dividend, we add a zero to the remainder making it 500, and continue the process.

On to step 13:
500 divided by 91 is 5 with a remainder of 45.
Write down 5 as next digit of the result. 
Result so far: 6911.5494505
Subtracting 455 from 500 leaves us with 45.
Since there are no more digits in the dividend, we add a zero to the remainder making it 450, and continue the process.

Let's proceed to step 14:
91 goes into 450 4 times with a remainder of 86.
Record the quotient 4 as the next digit in the result. 
Result so far: 6911.54945054
Subtract 364 from 450 to get 86.
Since there are no more digits in the dividend, we add a zero to the remainder making it 860, and continue the process.

The final result is 6911.54945054 with a remainder of 8.6e-08.