817783 ÷ 91 
The aim is to understand the frequency of 91 in 817783.

On to step 1:
If we divide 8 by 91, we get 0 and a remainder of 8.
Put 0 as the next digit of the answer. 
Result so far: 0.0
Deduct 0 from 8 and we're left with 8.
Grab the next digit (1) from the dividend, add it to 8, then carry on: 81 / 91

Let's proceed to step 2:
If we divide 81 by 91, we get 0 and a remainder of 81.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
Subtracting 0 from 81 leaves us with 81.
Take the next digit (7) from the dividend and append it to 81, then repeat: 817 / 91

Going ahead to step 3:
If we divide 817 by 91, we get 8 and a remainder of 89.
Use 8 as the next digit of our solution. 
Result so far: 8.0
The remainder is 89 after subtracting 728 from 817.
Grab the next digit (7) from the dividend, add it to 89, then carry on: 897 / 91

Moving on to step 4:
91 can be fit into 897 9 times, resulting in a remainder of 78.
Use 9 as the next digit of our solution. 
Result so far: 89.0
The remainder is 78 after subtracting 819 from 897.
Grab the next digit (8) from the dividend, add it to 78, then carry on: 788 / 91

Advancing to step 5:
91 goes into 788 8 times with a remainder of 60.
Write down 8 as next digit of the result. 
Result so far: 898.0
Deduct 728 from 788 and we're left with 60.
Grab the next digit (3) from the dividend, add it to 60, then carry on: 603 / 91

Moving on to step 6:
When dividing 603 by 91, we get 6 with a remainder of 57.
Record the quotient 6 as the next digit in the result. 
Result so far: 8986.0
The remainder is 57 after subtracting 546 from 603.
Since there are no more digits in the dividend, we add a zero to the remainder making it 570, and continue the process.

Moving on to step 7:
91 goes into 570 6 times with a remainder of 24.
Put 6 as the next digit of the answer. 
Result so far: 8986.6
Subtract 546 from 570 to get 24.
Since there are no more digits in the dividend, we add a zero to the remainder making it 240, and continue the process.

Advancing to step 8:
91 can be fit into 240 2 times, resulting in a remainder of 58.
Record the quotient 2 as the next digit in the result. 
Result so far: 8986.62
Subtracting 182 from 240 leaves us with 58.
Since there are no more digits in the dividend, we add a zero to the remainder making it 580, and continue the process.

Advancing to step 9:
580 divided by 91 is 6 with a remainder of 34.
Put 6 as the next digit of the answer. 
Result so far: 8986.626
Subtract 546 from 580 to get 34.
Since there are no more digits in the dividend, we add a zero to the remainder making it 340, and continue the process.

Step 10:
If we divide 340 by 91, we get 3 and a remainder of 67.
Write down 3 as next digit of the result. 
Result so far: 8986.6263
If we take 273 away from 340, we end up with 67.
Since there are no more digits in the dividend, we add a zero to the remainder making it 670, and continue the process.

On to step 11:
670 divided by 91 is 7 with a remainder of 33.
The next digit of our result is 7. 
Result so far: 8986.62637
If we take 637 away from 670, we end up with 33.
Since there are no more digits in the dividend, we add a zero to the remainder making it 330, and continue the process.

Moving on to step 12:
If we divide 330 by 91, we get 3 and a remainder of 57.
Put 3 as the next digit of the answer. 
Result so far: 8986.626373
If we take 273 away from 330, we end up with 57.
Since there are no more digits in the dividend, we add a zero to the remainder making it 570, and continue the process.

Going ahead to step 13:
570 divided by 91 is 6 with a remainder of 24.
The number 6 becomes the next digit in our result. 
Result so far: 8986.6263736
If we take 546 away from 570, we end up with 24.
Since there are no more digits in the dividend, we add a zero to the remainder making it 240, and continue the process.

Let's proceed to step 14:
If we divide 240 by 91, we get 2 and a remainder of 58.
Record the quotient 2 as the next digit in the result. 
Result so far: 8986.62637362
If we take 182 away from 240, we end up with 58.
Since there are no more digits in the dividend, we add a zero to the remainder making it 580, and continue the process.

Our division results in 8986.62637362 with a remaining 5.8e-08.