Let's divide 398991 by 28
The aim is to understand the frequency of 28 in 398991.

Step 1:
28 goes into 3 0 times with a remainder of 3.
Use 0 as the next digit of our solution. 
Result so far: 0.0
Deduct 0 from 3 and we're left with 3.
Append the next digit (9) from the dividend to 3 and continue with: 39 / 28

On to step 2:
The number 28 fits into 39 1 times, leaving a remainder of 11.
Record the quotient 1 as the next digit in the result. 
Result so far: 1.0
Subtract 28 from 39 to get 11.
Append the next digit (8) from the dividend to 11 and continue with: 118 / 28

Going ahead to step 3:
If we divide 118 by 28, we get 4 and a remainder of 6.
Write down 4 as next digit of the result. 
Result so far: 14.0
Deduct 112 from 118 and we're left with 6.
Grab the next digit (9) from the dividend, add it to 6, then carry on: 69 / 28

On to step 4:
If we divide 69 by 28, we get 2 and a remainder of 13.
Put 2 as the next digit of the answer. 
Result so far: 142.0
If we take 56 away from 69, we end up with 13.
Bring next digit (9) of the dividend behind the 13 and repeat the process: 139 / 28

Going ahead to step 5:
139 divided by 28 is 4 with a remainder of 27.
Record the quotient 4 as the next digit in the result. 
Result so far: 1424.0
Subtracting 112 from 139 leaves us with 27.
Include the next digit (1) from the dividend after 27, then repeat: 271 / 28

Advancing to step 6:
If we divide 271 by 28, we get 9 and a remainder of 19.
Record the quotient 9 as the next digit in the result. 
Result so far: 14249.0
If we subtract 252 from 271, we get 19.
Since there are no more digits in the dividend, we add a zero to the remainder making it 190, and continue the process.

Advancing to step 7:
When dividing 190 by 28, we get 6 with a remainder of 22.
The number 6 becomes the next digit in our result. 
Result so far: 14249.6
Subtracting 168 from 190 leaves us with 22.
Since there are no more digits in the dividend, we add a zero to the remainder making it 220, and continue the process.

On to step 8:
220 divided by 28 is 7 with a remainder of 24.
Put 7 as the next digit of the answer. 
Result so far: 14249.67
Deduct 196 from 220 and we're left 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.

Moving on to step 9:
28 can be fit into 240 8 times, resulting in a remainder of 16.
Write down 8 as next digit of the result. 
Result so far: 14249.678
The remainder is 16 after subtracting 224 from 240.
Since there are no more digits in the dividend, we add a zero to the remainder making it 160, and continue the process.

On to step 10:
When dividing 160 by 28, we get 5 with a remainder of 20.
Put 5 as the next digit of the answer. 
Result so far: 14249.6785
Subtract 140 from 160 to get 20.
Since there are no more digits in the dividend, we add a zero to the remainder making it 200, and continue the process.

On to step 11:
When dividing 200 by 28, we get 7 with a remainder of 4.
The next digit of our result is 7. 
Result so far: 14249.67857
Deduct 196 from 200 and we're left with 4.
Since there are no more digits in the dividend, we add a zero to the remainder making it 40, and continue the process.

Going ahead to step 12:
If we divide 40 by 28, we get 1 and a remainder of 12.
Record the quotient 1 as the next digit in the result. 
Result so far: 14249.678571
If we take 28 away from 40, 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.

Step 13:
120 divided by 28 is 4 with a remainder of 8.
Write down 4 as next digit of the result. 
Result so far: 14249.6785714
The remainder is 8 after subtracting 112 from 120.
Since there are no more digits in the dividend, we add a zero to the remainder making it 80, and continue the process.

Advancing to step 14:
80 divided by 28 is 2 with a remainder of 24.
Use 2 as the next digit of our solution. 
Result so far: 14249.67857142
Subtracting 56 from 80 leaves us 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.

In conclusion, the division gives 14249.67857142 with a balance of 2.4e-08.