Let's divide 643486 by 28
The aim is to understand the frequency of 28 in 643486.

Going ahead to step 1:
When dividing 6 by 28, we get 0 with a remainder of 6.
Use 0 as the next digit of our solution. 
Result so far: 0.0
Subtracting 0 from 6 leaves us with 6.
Bring next digit (4) of the dividend behind the 6 and repeat the process: 64 / 28

Step 2:
28 goes into 64 2 times with a remainder of 8.
Put 2 as the next digit of the answer. 
Result so far: 2.0
Subtract 56 from 64 to get 8.
Append the next digit (3) from the dividend to 8 and continue with: 83 / 28

On to step 3:
The number 28 fits into 83 2 times, leaving a remainder of 27.
Use 2 as the next digit of our solution. 
Result so far: 22.0
Subtracting 56 from 83 leaves us with 27.
Include the next digit (4) from the dividend after 27, then repeat: 274 / 28

Advancing to step 4:
The number 28 fits into 274 9 times, leaving a remainder of 22.
Write down 9 as next digit of the result. 
Result so far: 229.0
Deduct 252 from 274 and we're left with 22.
Take the next digit (8) from the dividend and append it to 22, then repeat: 228 / 28

Moving on to step 5:
228 divided by 28 is 8 with a remainder of 4.
Use 8 as the next digit of our solution. 
Result so far: 2298.0
Subtracting 224 from 228 leaves us with 4.
Grab the next digit (6) from the dividend, add it to 4, then carry on: 46 / 28

Going ahead to step 6:
28 goes into 46 1 times with a remainder of 18.
The number 1 becomes the next digit in our result. 
Result so far: 22981.0
The remainder is 18 after subtracting 28 from 46.
Since there are no more digits in the dividend, we add a zero to the remainder making it 180, and continue the process.

On to step 7:
28 goes into 180 6 times with a remainder of 12.
Write down 6 as next digit of the result. 
Result so far: 22981.6
The remainder is 12 after subtracting 168 from 180.
Since there are no more digits in the dividend, we add a zero to the remainder making it 120, and continue the process.

On to step 8:
When dividing 120 by 28, we get 4 with a remainder of 8.
Use 4 as the next digit of our solution. 
Result so far: 22981.64
If we take 112 away from 120, we end up with 8.
Since there are no more digits in the dividend, we add a zero to the remainder making it 80, and continue the process.

Moving on to step 9:
The number 28 fits into 80 2 times, leaving a remainder of 24.
The next digit of our result is 2. 
Result so far: 22981.642
The remainder is 24 after subtracting 56 from 80.
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 10:
28 can be fit into 240 8 times, resulting in a remainder of 16.
Put 8 as the next digit of the answer. 
Result so far: 22981.6428
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 11:
The number 28 fits into 160 5 times, leaving a remainder of 20.
Put 5 as the next digit of the answer. 
Result so far: 22981.64285
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.

Step 12:
The number 28 fits into 200 7 times, leaving a remainder of 4.
Write down 7 as next digit of the result. 
Result so far: 22981.642857
If we take 196 away from 200, we end up 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.

Step 13:
When dividing 40 by 28, we get 1 with a remainder of 12.
Use 1 as the next digit of our solution. 
Result so far: 22981.6428571
The remainder is 12 after subtracting 28 from 40.
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:
When dividing 120 by 28, we get 4 with a remainder of 8.
The next digit of our result is 4. 
Result so far: 22981.64285714
If we subtract 112 from 120, we get 8.
Since there are no more digits in the dividend, we add a zero to the remainder making it 80, and continue the process.

In conclusion, the division gives 22981.64285714 with a balance of 8e-09.