We're dividing 958661 by 91 
The aim is to understand the frequency of 91 in 958661.

On to step 1:
When dividing 9 by 91, we get 0 with a remainder of 9.
Put 0 as the next digit of the answer. 
Result so far: 0.0
Subtracting 0 from 9 leaves us with 9.
Fetch the next digit (5) from the dividend, attach it to 9 and continue: 95 / 91

Let's proceed to step 2:
The number 91 fits into 95 1 times, leaving a remainder of 4.
The number 1 becomes the next digit in our result. 
Result so far: 1.0
Deduct 91 from 95 and we're left with 4.
Fetch the next digit (8) from the dividend, attach it to 4 and continue: 48 / 91

Advancing to step 3:
The number 91 fits into 48 0 times, leaving a remainder of 48.
The next digit of our result is 0. 
Result so far: 10.0
If we subtract 0 from 48, we get 48.
Bring next digit (6) of the dividend behind the 48 and repeat the process: 486 / 91

Moving on to step 4:
91 can be fit into 486 5 times, resulting in a remainder of 31.
Use 5 as the next digit of our solution. 
Result so far: 105.0
Deduct 455 from 486 and we're left with 31.
Bring next digit (6) of the dividend behind the 31 and repeat the process: 316 / 91

Let's proceed to step 5:
91 goes into 316 3 times with a remainder of 43.
Use 3 as the next digit of our solution. 
Result so far: 1053.0
If we subtract 273 from 316, we get 43.
Grab the next digit (1) from the dividend, add it to 43, then carry on: 431 / 91

Advancing to step 6:
91 can be fit into 431 4 times, resulting in a remainder of 67.
Write down 4 as next digit of the result. 
Result so far: 10534.0
Subtract 364 from 431 to get 67.
Since there are no more digits in the dividend, we add a zero to the remainder making it 670, and continue the process.

Going ahead to step 7:
If we divide 670 by 91, we get 7 and a remainder of 33.
Write down 7 as next digit of the result. 
Result so far: 10534.7
Subtract 637 from 670 to get 33.
Since there are no more digits in the dividend, we add a zero to the remainder making it 330, and continue the process.

Let's proceed to step 8:
91 can be fit into 330 3 times, resulting in a remainder of 57.
The next digit of our result is 3. 
Result so far: 10534.73
The remainder is 57 after subtracting 273 from 330.
Since there are no more digits in the dividend, we add a zero to the remainder making it 570, and continue the process.

Let's proceed to step 9:
The number 91 fits into 570 6 times, leaving a remainder of 24.
Write down 6 as next digit of the result. 
Result so far: 10534.736
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.

Advancing to step 10:
91 goes into 240 2 times with a remainder of 58.
The next digit of our result is 2. 
Result so far: 10534.7362
The remainder is 58 after subtracting 182 from 240.
Since there are no more digits in the dividend, we add a zero to the remainder making it 580, and continue the process.

Going ahead to step 11:
The number 91 fits into 580 6 times, leaving a remainder of 34.
Write down 6 as next digit of the result. 
Result so far: 10534.73626
If we take 546 away from 580, we end up with 34.
Since there are no more digits in the dividend, we add a zero to the remainder making it 340, and continue the process.

Going ahead to step 12:
The number 91 fits into 340 3 times, leaving a remainder of 67.
Put 3 as the next digit of the answer. 
Result so far: 10534.736263
If we subtract 273 from 340, we get 67.
Since there are no more digits in the dividend, we add a zero to the remainder making it 670, and continue the process.

Step 13:
When dividing 670 by 91, we get 7 with a remainder of 33.
Use 7 as the next digit of our solution. 
Result so far: 10534.7362637
Subtracting 637 from 670 leaves us 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 14:
330 divided by 91 is 3 with a remainder of 57.
The number 3 becomes the next digit in our result. 
Result so far: 10534.73626373
The remainder is 57 after subtracting 273 from 330.
Since there are no more digits in the dividend, we add a zero to the remainder making it 570, and continue the process.

The final outcome is 10534.73626373, with a leftover of 5.7e-08.