We look at the division of 223161 by 91 
The aim is to understand the frequency of 91 in 223161.

Step 1:
2 divided by 91 is 0 with a remainder of 2.
Write down 0 as next digit of the result. 
Result so far: 0.0
Subtract 0 from 2 to get 2.
Include the next digit (2) from the dividend after 2, then repeat: 22 / 91

Let's proceed to step 2:
91 can be fit into 22 0 times, resulting in a remainder of 22.
The number 0 becomes the next digit in our result. 
Result so far: 0.0
Subtract 0 from 22 to get 22.
Grab the next digit (3) from the dividend, add it to 22, then carry on: 223 / 91

Step 3:
223 divided by 91 is 2 with a remainder of 41.
Use 2 as the next digit of our solution. 
Result so far: 2.0
The remainder is 41 after subtracting 182 from 223.
Fetch the next digit (1) from the dividend, attach it to 41 and continue: 411 / 91

Advancing to step 4:
If we divide 411 by 91, we get 4 and a remainder of 47.
The next digit of our result is 4. 
Result so far: 24.0
Subtract 364 from 411 to get 47.
Bring next digit (6) of the dividend behind the 47 and repeat the process: 476 / 91

Step 5:
When dividing 476 by 91, we get 5 with a remainder of 21.
The number 5 becomes the next digit in our result. 
Result so far: 245.0
If we subtract 455 from 476, we get 21.
Append the next digit (1) from the dividend to 21 and continue with: 211 / 91

Advancing to step 6:
91 goes into 211 2 times with a remainder of 29.
The next digit of our result is 2. 
Result so far: 2452.0
Subtract 182 from 211 to get 29.
Since there are no more digits in the dividend, we add a zero to the remainder making it 290, and continue the process.

Advancing to step 7:
290 divided by 91 is 3 with a remainder of 17.
The number 3 becomes the next digit in our result. 
Result so far: 2452.3
Subtract 273 from 290 to get 17.
Since there are no more digits in the dividend, we add a zero to the remainder making it 170, and continue the process.

Moving on to step 8:
If we divide 170 by 91, we get 1 and a remainder of 79.
Put 1 as the next digit of the answer. 
Result so far: 2452.31
Subtract 91 from 170 to get 79.
Since there are no more digits in the dividend, we add a zero to the remainder making it 790, and continue the process.

On to step 9:
790 divided by 91 is 8 with a remainder of 62.
The next digit of our result is 8. 
Result so far: 2452.318
The remainder is 62 after subtracting 728 from 790.
Since there are no more digits in the dividend, we add a zero to the remainder making it 620, and continue the process.

Moving on to step 10:
620 divided by 91 is 6 with a remainder of 74.
Use 6 as the next digit of our solution. 
Result so far: 2452.3186
If we take 546 away from 620, we end up with 74.
Since there are no more digits in the dividend, we add a zero to the remainder making it 740, and continue the process.

Step 11:
The number 91 fits into 740 8 times, leaving a remainder of 12.
Write down 8 as next digit of the result. 
Result so far: 2452.31868
If we take 728 away from 740, we end up with 12.
Since there are no more digits in the dividend, we add a zero to the remainder making it 120, and continue the process.

Advancing to step 12:
When dividing 120 by 91, we get 1 with a remainder of 29.
Record the quotient 1 as the next digit in the result. 
Result so far: 2452.318681
If we take 91 away from 120, we end up with 29.
Since there are no more digits in the dividend, we add a zero to the remainder making it 290, and continue the process.

Let's proceed to step 13:
91 goes into 290 3 times with a remainder of 17.
Write down 3 as next digit of the result. 
Result so far: 2452.3186813
Subtract 273 from 290 to get 17.
Since there are no more digits in the dividend, we add a zero to the remainder making it 170, and continue the process.

Step 14:
If we divide 170 by 91, we get 1 and a remainder of 79.
Write down 1 as next digit of the result. 
Result so far: 2452.31868131
If we subtract 91 from 170, we get 79.
Since there are no more digits in the dividend, we add a zero to the remainder making it 790, and continue the process.

In conclusion, the division gives 2452.31868131 with a balance of 7.9e-08.