880590 divided by 91 
The aim is to understand the frequency of 91 in 880590.

On to step 1:
The number 91 fits into 8 0 times, leaving a remainder of 8.
The number 0 becomes the next digit in our result. 
Result so far: 0.0
The remainder is 8 after subtracting 0 from 8.
Fetch the next digit (8) from the dividend, attach it to 8 and continue: 88 / 91

Step 2:
91 can be fit into 88 0 times, resulting in a remainder of 88.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
If we take 0 away from 88, we end up with 88.
Append the next digit (0) from the dividend to 88 and continue with: 880 / 91

Advancing to step 3:
880 divided by 91 is 9 with a remainder of 61.
Write down 9 as next digit of the result. 
Result so far: 9.0
Subtract 819 from 880 to get 61.
Bring next digit (5) of the dividend behind the 61 and repeat the process: 615 / 91

Let's proceed to step 4:
The number 91 fits into 615 6 times, leaving a remainder of 69.
Use 6 as the next digit of our solution. 
Result so far: 96.0
Deduct 546 from 615 and we're left with 69.
Append the next digit (9) from the dividend to 69 and continue with: 699 / 91

Going ahead to step 5:
When dividing 699 by 91, we get 7 with a remainder of 62.
Write down 7 as next digit of the result. 
Result so far: 967.0
If we subtract 637 from 699, we get 62.
Fetch the next digit (0) from the dividend, attach it to 62 and continue: 620 / 91

Going ahead to step 6:
91 goes into 620 6 times with a remainder of 74.
Write down 6 as next digit of the result. 
Result so far: 9676.0
If we subtract 546 from 620, we get 74.
Since there are no more digits in the dividend, we add a zero to the remainder making it 740, and continue the process.

Moving on to step 7:
When dividing 740 by 91, we get 8 with a remainder of 12.
Use 8 as the next digit of our solution. 
Result so far: 9676.8
The remainder is 12 after subtracting 728 from 740.
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 8:
If we divide 120 by 91, we get 1 and a remainder of 29.
Write down 1 as next digit of the result. 
Result so far: 9676.81
Deduct 91 from 120 and we're left 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.

On to step 9:
91 can be fit into 290 3 times, resulting in a remainder of 17.
The next digit of our result is 3. 
Result so far: 9676.813
Subtracting 273 from 290 leaves us with 17.
Since there are no more digits in the dividend, we add a zero to the remainder making it 170, and continue the process.

Advancing to step 10:
170 divided by 91 is 1 with a remainder of 79.
Use 1 as the next digit of our solution. 
Result so far: 9676.8131
The remainder is 79 after subtracting 91 from 170.
Since there are no more digits in the dividend, we add a zero to the remainder making it 790, and continue the process.

Advancing to step 11:
790 divided by 91 is 8 with a remainder of 62.
Put 8 as the next digit of the answer. 
Result so far: 9676.81318
Deduct 728 from 790 and we're left with 62.
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 12:
The number 91 fits into 620 6 times, leaving a remainder of 74.
Put 6 as the next digit of the answer. 
Result so far: 9676.813186
Subtracting 546 from 620 leaves us 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 13:
740 divided by 91 is 8 with a remainder of 12.
Put 8 as the next digit of the answer. 
Result so far: 9676.8131868
If we subtract 728 from 740, we get 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 14:
91 goes into 120 1 times with a remainder of 29.
The number 1 becomes the next digit in our result. 
Result so far: 9676.81318681
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.

The quotient of the division is 9676.81318681, and the remainder is 2.9e-08.