81105909 ÷ 813 
The aim is to understand the frequency of 813 in 81105909.

On to step 1:
If we divide 8 by 813, we get 0 and a remainder of 8.
Write down 0 as next digit of the result. 
Result so far: 0.0
Subtracting 0 from 8 leaves us with 8.
Bring next digit (1) of the dividend behind the 8 and repeat the process: 81 / 813

Step 2:
If we divide 81 by 813, we get 0 and a remainder of 81.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
Subtract 0 from 81 to get 81.
Take the next digit (1) from the dividend and append it to 81, then repeat: 811 / 813

On to step 3:
813 can be fit into 811 0 times, resulting in a remainder of 811.
Write down 0 as next digit of the result. 
Result so far: 0.0
Subtract 0 from 811 to get 811.
Grab the next digit (0) from the dividend, add it to 811, then carry on: 8110 / 813

Step 4:
813 goes into 8110 9 times with a remainder of 793.
Use 9 as the next digit of our solution. 
Result so far: 9.0
If we take 7317 away from 8110, we end up with 793.
Grab the next digit (5) from the dividend, add it to 793, then carry on: 7935 / 813

Advancing to step 5:
When dividing 7935 by 813, we get 9 with a remainder of 618.
The next digit of our result is 9. 
Result so far: 99.0
If we take 7317 away from 7935, we end up with 618.
Grab the next digit (9) from the dividend, add it to 618, then carry on: 6189 / 813

Going ahead to step 6:
6189 divided by 813 is 7 with a remainder of 498.
Put 7 as the next digit of the answer. 
Result so far: 997.0
The remainder is 498 after subtracting 5691 from 6189.
Append the next digit (0) from the dividend to 498 and continue with: 4980 / 813

Moving on to step 7:
813 goes into 4980 6 times with a remainder of 102.
The next digit of our result is 6. 
Result so far: 9976.0
Subtracting 4878 from 4980 leaves us with 102.
Grab the next digit (9) from the dividend, add it to 102, then carry on: 1029 / 813

Advancing to step 8:
1029 divided by 813 is 1 with a remainder of 216.
Write down 1 as next digit of the result. 
Result so far: 99761.0
The remainder is 216 after subtracting 813 from 1029.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2160, and continue the process.

Advancing to step 9:
813 goes into 2160 2 times with a remainder of 534.
Put 2 as the next digit of the answer. 
Result so far: 99761.2
If we subtract 1626 from 2160, we get 534.
Since there are no more digits in the dividend, we add a zero to the remainder making it 5340, and continue the process.

Going ahead to step 10:
813 can be fit into 5340 6 times, resulting in a remainder of 462.
Record the quotient 6 as the next digit in the result. 
Result so far: 99761.26
If we take 4878 away from 5340, we end up with 462.
Since there are no more digits in the dividend, we add a zero to the remainder making it 4620, and continue the process.

Step 11:
4620 divided by 813 is 5 with a remainder of 555.
The number 5 becomes the next digit in our result. 
Result so far: 99761.265
The remainder is 555 after subtracting 4065 from 4620.
Since there are no more digits in the dividend, we add a zero to the remainder making it 5550, and continue the process.

Let's proceed to step 12:
813 goes into 5550 6 times with a remainder of 672.
The number 6 becomes the next digit in our result. 
Result so far: 99761.2656
Deduct 4878 from 5550 and we're left with 672.
Since there are no more digits in the dividend, we add a zero to the remainder making it 6720, and continue the process.

Going ahead to step 13:
813 can be fit into 6720 8 times, resulting in a remainder of 216.
The number 8 becomes the next digit in our result. 
Result so far: 99761.26568
If we subtract 6504 from 6720, we get 216.
Since there are no more digits in the dividend, we add a zero to the remainder making it 2160, and continue the process.

Going ahead to step 14:
2160 divided by 813 is 2 with a remainder of 534.
Record the quotient 2 as the next digit in the result. 
Result so far: 99761.265682
If we subtract 1626 from 2160, we get 534.
Since there are no more digits in the dividend, we add a zero to the remainder making it 5340, and continue the process.

Let's proceed to step 15:
When dividing 5340 by 813, we get 6 with a remainder of 462.
Record the quotient 6 as the next digit in the result. 
Result so far: 99761.2656826
If we take 4878 away from 5340, we end up with 462.
Since there are no more digits in the dividend, we add a zero to the remainder making it 4620, and continue the process.

Going ahead to step 16:
4620 divided by 813 is 5 with a remainder of 555.
Put 5 as the next digit of the answer. 
Result so far: 99761.26568265
The remainder is 555 after subtracting 4065 from 4620.
Since there are no more digits in the dividend, we add a zero to the remainder making it 5550, and continue the process.

In conclusion, the division gives 99761.26568265 with a balance of 5.55e-07.