We look at the division of 640622 by 28 
The aim is to understand the frequency of 28 in 640622.

Going ahead to step 1:
6 divided by 28 is 0 with a remainder of 6.
The next digit of our result is 0. 
Result so far: 0.0
Deduct 0 from 6 and we're left with 6.
Grab the next digit (4) from the dividend, add it to 6, then carry on: 64 / 28

Let's proceed to step 2:
64 divided by 28 is 2 with a remainder of 8.
Write down 2 as next digit of the result. 
Result so far: 2.0
If we subtract 56 from 64, we get 8.
Fetch the next digit (0) from the dividend, attach it to 8 and continue: 80 / 28

Step 3:
If we divide 80 by 28, we get 2 and a remainder of 24.
Put 2 as the next digit of the answer. 
Result so far: 22.0
If we subtract 56 from 80, we get 24.
Include the next digit (6) from the dividend after 24, then repeat: 246 / 28

Moving on to step 4:
The number 28 fits into 246 8 times, leaving a remainder of 22.
Write down 8 as next digit of the result. 
Result so far: 228.0
Deduct 224 from 246 and we're left with 22.
Include the next digit (2) from the dividend after 22, then repeat: 222 / 28

Going ahead to step 5:
The number 28 fits into 222 7 times, leaving a remainder of 26.
Put 7 as the next digit of the answer. 
Result so far: 2287.0
Subtract 196 from 222 to get 26.
Include the next digit (2) from the dividend after 26, then repeat: 262 / 28

Let's proceed to step 6:
28 goes into 262 9 times with a remainder of 10.
Record the quotient 9 as the next digit in the result. 
Result so far: 22879.0
The remainder is 10 after subtracting 252 from 262.
Since there are no more digits in the dividend, we add a zero to the remainder making it 100, and continue the process.

Let's proceed to step 7:
When dividing 100 by 28, we get 3 with a remainder of 16.
Record the quotient 3 as the next digit in the result. 
Result so far: 22879.3
Deduct 84 from 100 and we're left with 16.
Since there are no more digits in the dividend, we add a zero to the remainder making it 160, and continue the process.

Advancing to step 8:
28 goes into 160 5 times with a remainder of 20.
The number 5 becomes the next digit in our result. 
Result so far: 22879.35
Deduct 140 from 160 and we're left with 20.
Since there are no more digits in the dividend, we add a zero to the remainder making it 200, and continue the process.

Advancing to step 9:
When dividing 200 by 28, we get 7 with a remainder of 4.
The next digit of our result is 7. 
Result so far: 22879.357
If we subtract 196 from 200, we get 4.
Since there are no more digits in the dividend, we add a zero to the remainder making it 40, and continue the process.

On to step 10:
28 goes into 40 1 times with a remainder of 12.
Use 1 as the next digit of our solution. 
Result so far: 22879.3571
Subtract 28 from 40 to 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.

On to step 11:
28 goes into 120 4 times with a remainder of 8.
Use 4 as the next digit of our solution. 
Result so far: 22879.35714
Subtracting 112 from 120 leaves us 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 12:
28 can be fit into 80 2 times, resulting in a remainder of 24.
The number 2 becomes the next digit in our result. 
Result so far: 22879.357142
Subtract 56 from 80 to get 24.
Since there are no more digits in the dividend, we add a zero to the remainder making it 240, and continue the process.

Let's proceed to step 13:
When dividing 240 by 28, we get 8 with a remainder of 16.
The next digit of our result is 8. 
Result so far: 22879.3571428
If we take 224 away from 240, we end up with 16.
Since there are no more digits in the dividend, we add a zero to the remainder making it 160, and continue the process.

Going ahead to step 14:
28 goes into 160 5 times with a remainder of 20.
The next digit of our result is 5. 
Result so far: 22879.35714285
Deduct 140 from 160 and we're left with 20.
Since there are no more digits in the dividend, we add a zero to the remainder making it 200, and continue the process.

The final outcome is 22879.35714285, with a leftover of 2e-08.